How To Remove Cloudy Water In Fish Tank

Eric is an aquarium enthusiast with over 2 decades of experience caring for a wide array of tropical fish.

Avoid a cloudy fish tank and keep your water crystal clear by practicing good aquarium maintenance habits. — Avoid a cloudy fish tank and go along your water crystal articulate by practicing practiced aquarium maintenance habits.

What Causes Cloudy Water?

When the h2o in your aquarium turns cloudy and your love fish disappear into a hazy fog it is easy to get frustrated. Sometimes the reasons why your tank went from fish heaven to fish apocalypse may exist every bit clouded as the tank h2o itself.

Rest assured, tank water does not change so drastically without reason. This ways you probably did something wrong. But it besides means that, once y'all empathize your error, you can modify your tank direction practices and greatly reduce the chances of it happening again.

In this article, you lot will read nigh v common reasons fish tanks plough cloudy. One or several of these causes may exist at the root of what has happened to your tank. In many cases, these problems are easy to solve, and if you act soon enough your fish should pull through without any problem.

Two Cardinal Takeaways From This Article

Throughout this article, you lot will come across two pieces of communication repeated no matter the cause of your cloudy water. First, you need to perform a partial water change. This will dilute the dissolved chemicals and waste matter in the h2o and make it a safer surroundings for your fish.

While it may be tempting to remove all or most of the water in an try to articulate things up, this tin can potentially make things worse. A 25% water alter is a good starting bespeak.

Second, use a gravel vacuum to make clean the gravel and remove as much of the fish waste and decomposable matter equally possible. When this junk is left to accrue on the substrate it can eventually crusade tank-wide issues. With well-nigh of the good vacuum systems, you can modify the water and clean the gravel at the same time.

Regular water changes and gravel vacuuming are two of the virtually important duties of your aquarium care routine. However, there are often other factors that can make your tank water turn cloudy, and unless you lot eliminate the problem it is probable to occur again.

As you will see, some of the issues that cause an aquarium to plough murky are symptoms of greater issues.

one. Bacterial Flower

We'll start with the virtually mutual issue that may have turned your tank cloudy: Bacterial flower. Decaying nutrient and fish waste provide a rich source of nutrients for bacterial growth. A bacterial bloom usually appears as a milky brume.

Leaner in your tank isn't a bad thing. In fact, it is needed to break down waste and maintain good for you water weather. The balance between microorganisms and the fish in your tank is what keeps harmful chemicals under control.

Merely when something tips the scales and the bacterial colonies in your tank can't get the job washed, that'due south when h2o quality suffers. Waste builds up, and the bacterial population suddenly explodes with the abundance of nutrient.

Nearly usually, a bacterial bloom occurs when a new tank hasn't been cycled properly, or when a massive h2o modify and aquarium cleaning results in a mini-cycle equally the bacterial colonies in your tank become through a stage of re-population.

This is a big reason why you e'er perform partial water changes when performing regular tank maintenance: You don't want to remove likewise many of the microorganisms that are keeping your tank healthy.

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two. Overfeeding

Feeding your fish besides much and too often in itself can cause water cloudiness. This may be due to food particulates dissolved in the h2o, a bacterial bloom, or both.

The instructions on many fish-nutrient containers tell y'all to feed multiple times per 24-hour interval. That's fine, but if you are going to do that yous really need to get a handle on how much your fish are eating, and how much is globe-trotting to the bottom of the tank. Uneaten food decays, and plenty of it can cloud the water.

This can happen in a large tank, simply it is also the kind of effect that ofttimes happens to well-meaning betta owners. 1 little betta fish does non eat a whole lot of food, and then giving him a pinch of fish flakes or a couple of betta pellets a few times a twenty-four hours volition shortly pollute his little tank.

How to Eliminate Cloudy Water Due to Overfeeding

To remedy this problem perform a fractional h2o alter and vacuum the gravel in order to clean up the tank and make it safer for your fish. Then, y'all demand to reevaluate how you are feeding.

I prefer to feed once per twenty-four hours and permit them one twenty-four hour period of fasting per week. This is healthier for your fish than overfeeding and will assistance keep your tank cleaner. Remember, some of what goes into a fish is eventually going to come back out. Feeding too much food not only means more decaying, uneaten food in the tank, but also more fish waste.

three. Overstocking

Overstocked fish tanks accept multiple problems. Aside from behavior clashes and stress for the fish themselves, the tank weather in an overstocked tank can often deteriorate to a toxic surround which can event in cloudy tank h2o.

To sympathise the trouble, think of your tank as a little ecosystem, something like a tiny lake. Your tank has microorganisms that aid to break down waste, and the filter system plays the role of the streams and springs that cleanse a lake and aerate the h2o.

But every bit a lake can only support so much life, the same is true of your tank. A lake is more resilient because information technology has the reward of a constant supply of fresh, clean h2o. But, because your tank is a closed ecosystem with no fresh water coming in, once things are out of whack information technology is unable to regain that balance without your intervention.

How to Go Rid of Cloudy H2o in an Overstocked Tank

Some fish keepers make up for overstocking by over-filtering and keeping a heavily planted tank. Both of those things help, but ultimately the solution is to continue your stock downward to a level that the tank tin maintain.

Perform a water change and vacuum the gravel to become things back somewhere shut to normal, only and so find a way to re-home some of those fish.

Algae growth is typical in aquariums, but a sudden algae bloom can turn your water a murky green. — Algae growth is typical in aquariums, but a sudden algae flower can turn your h2o a murky green.

iv. Algae Flower

If you accept run an aquarium for any amount of fourth dimension you are probable well enlightened of algae issues. These establish-similar organisms abound on your decorations and the sides of your tank, and left unchecked tin turn your tank into a light-green mess. Algae blooms frequently announced as a greenish hue.

Algae thrive on the same things that plants beloved: Nutrient in the form of nitrogen and sunlight. If you are having a problem with algae blooms in your tank the cause is probably related to one of those 2 factors.

A sudden spike in nitrogen in the form of excessive feeding and/or fish waste (see above) may also cause a sudden algae bloom. Remember that algae aren't just a nuisance, they are living organisms in your tank and therefore impact the ecosystem just like fish or plants. If you lot do zilch a sudden increase in algae tin upset the rest of your tank, and this is bad for your fish.

Another reason you may experience frequent algae blooms has to do with your tank placement. Your tank should not be hit by direct sunlight during the course of the solar day. If information technology is, this gives algae some added energy to get growing. Remember, similar a plant, if it has food and sunlight it tin can thrive.

How to Clear Up Aquarium H2o Afterward Algae Bloom

The solution to an algae flower is to perform a h2o alter and so remedy any situation caused the blossom. This ways either get your feeding practices under control or motion your tank to a location where sunlight won't help algae run amok.

5. Driftwood Leaching Tannins

Here's a reason a tank may turn cloudy which really isn't a intendance mistake on your function, just may instead be due to a lack of knowledge of your tank decorations. Using natural driftwood in your tank is a swell idea. Information technology looks fantastic, and some fish will benefit from nibbling or rasping on it. Driftwood can also drop the pH of the tank water slightly, which is useful if your water source is a fleck hard similar mine.

Only if you've just added a new piece of driftwood to your tank you may observe your water has turned a yellowish tea-like color. This is because driftwood, particularly commercially available types like African Mopani, leaches tannins into the tank h2o.

This isn't probable to impairment your fish, so yous can wipe some sweat off your brow. But if you don't like the hue your tank has taken on considering of the tannins, but you do like the driftwood, there are a few things you can practise.

What to Do About Tannins

Common advice is to boil the driftwood before dropping it into your tank. Withal, sometimes the wood you lot have chosen is likewise large. In these cases, I've used a big storage container to soak a new piece of driftwood for several days earlier placing it in the tank. As with everything else that touches your tank, be sure to employ a container that does not have a buildup of detergents or other chemicals.

If y'all have carbon in your filter information technology can assist a little, and regular water changes (not more than than weekly) will gradually clear upward your water. Driftwood stops leaching tannins over time, and then eventually, this will finish to exist an effect.

4 Steps to Avoiding a Cloudy Tank

As yous've surely deduced by now, there are a handful of basic things yous tin can do to profoundly increase the chances that y'all never wake upward to an aquarium that has suddenly turned cloudy:

Keep upward with tank maintenance. This ways a regular schedule of water changes and gravel vacuuming.
Practise not overfeed your fish. Excess food ways more than waste.
Do not overstock your tank. Too many fish means your tank can't keep up with the processes required to proceed the water healthy.
Do not place your tank in direct sunlight. Just like plants, algae thrive in sunlight.

Of class, nosotros all stammer from time to time. Life gets decorated and yous neglect to perform simple aquarium maintenance chores, or a personal or business emergency takes your time away from your fish-keeping hobby. If this happens, all is non lost. Once things settle downward you can unremarkably become your tank dorsum on track.

This commodity is authentic and true to the best of the author's knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized communication from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.

Questions & Answers

Question: Should I accept stones in my fish tank?

Answer: Gravel is very of import in a fish tank, and y'all should accept nearly a pound of it for each gallon of water. The gravel not only makes for a more natural surroundings, but gives the good microbes a place to thrive in your tank. These microbes assist to manage waste product and proceed your water healthy. If you lot don't wish to have gravel, you lot can utilize sand or small pebbles every bit substrate for the bottom of your tank.

Every bit far as using stones for ornament, that's an aesthetic decision and totally up to you. Notwithstanding, I will circumspection you lot to only choose stones and rocks that are safe for aquarium utilize. One easy way to be sure of this is to only use stones you've purchased from a alive fish store or pet store, and that are specifically intended for use in aquariums.

Yous can too hunt for stones outdoors, merely beware that this can be potentially harmful to your fish. Some stones tin can have minerals or unsafe metals in them that will leach into the water. They may fifty-fifty accept mucus, parasites or pesticides. Then, if you practice cull rocks from your yard or garden, exist certain to do some research and find out what they are and if they are okay for aquarium use.

I have used rocks from the outdoors in my tanks before, only I wasn't very comfortable with it. My general rule of thumb is to merely put things in fish tanks that are fabricated to go in fish tanks.

Eric Dockett (author) from United states on September 04, 2020:

Hi Steve. It depends on what is causing your cloudy h2o. A partial water modify every few days may clear up your h2o temporarily. However, it is important to understand why you accept cloudy water and then you can forestall it in the hereafter. In some cases, changing the water or vaccuming the gravel too much can actually make information technology worse.

Steve Ward on September 03, 2020:

How often can i practice a water modify on my x gallon to become the h2o crystal clear again?

tracy brisch on June 02, 2020:

I hang some Philodendron clippings over the edge into my rasboras 10 gallon tank that exercise fantabulous and I actually trim dorsum the roots if they overgrow occasionally. After cleaning and replacing all water in tank with old filter h2o became cloudy overnight. After reading this commodity I removed the hat for more oxygen, and, I realized I had forgotten to add dorsum the Philodendron clippings! It was simply a thing of hours and water is absolutely clear! Thank you

jnsm41378 on February 16, 2019:

I have a 55 gal hexagon shaped tank. With 2 Black Moors, 2 shubunkin goldfish & ii algae eaters. Ive Had it upwards and running for 3+ months at present, I exercise the partial h2o changes and vacuum the gravel, I feed them twice a day. I have submersible h2o pump, 3 air stones run from the external air pump, external multi-stage power filter. Water tests fine on every level. No matter what I do, how frequent or infrequent, the water stays cloudy. Id say a milky deject. In the brusk amt of time I've had this aquarium, I've completely emptied and cleaned the unabridged tank twice, and by the next 24-hour interval or 2 its cloudy again. The fish seem to exist healthy, to me, they are pretty active and I accept to admit very social

Brandon on Jan 16, 2019:

I've had my tank for about a twelvemonth now, and it never got suddenly cloudy until at present. It seems to happen every time I change the filter. This has never happened earlier, just it's happening all the time now. Anyone know why?

footballogy on Jan 06, 2019:

Give thanks you lot, Eric.

Eric Dockett (author) from The states on January 06, 2019:

@footballology - I really appreciate the asking, but I prefer my original images remain exclusive to the articles for which I created them. Yous tin certainly reference the article if that helps you at all. Practiced luck with your book!

Eric Dockett (writer) from USA on December 28, 2018:

@Virgil - Did you thoroughly rinse the gravel before adding the h2o? If not that could be the reason for the cloudiness. Please research the nitrogen bike. You should bicycle your tank before calculation whatever fish.

Virgil D Irvin on Dec 27, 2018:

Merely got first 36 gal.tank put fifty lbs.gravel and filter filled with h2o turned on,side by side twenty-four hour period cloudy water no fish even so, how long should I wait before releasing the glo fish What should the water temp be

Eric Dockett (author) from United states of america on December 23, 2018:

@Nancy - I would get out the tank solitary for a trivial while and see if information technology clears up. It sounds like you are making a lot of changes and doing a lot of cleaning. He is also getting a little big for a thirty-gallon tank, and I'g wondering if that may be part of the consequence.

Eric Dockett (author) from United states of america on December 05, 2018:

@Kay - In that location could be a number of reasons for you lot readings, including excess feeding, overstocking and a tank that hasn't fully cycled. Yes, it could be why you h2o is cloudy.

@ FW - Puzzling. If you lot are adding bacteria later cleaning the gravel I am wondering if you are seeing a bacterial bloom a day or so after cleaning. Is that a possibility? It is so difficult to estimate when it is someone else'due south tank.

If you think that might be information technology, you may try letting it go a niggling while after it turns cloudy to see if it clears upward on its own. Just keep an eye on the h2o parameters.

FW Fishman on December 04, 2018:

7.0 ph, 0 nitrates, 0 nitrites, 0.2 ammonia, all is practiced.

kay on December 04, 2018:

My Nitrites and Nitrates are loftier what do I do to get them lower? And could that be why my water is cloudy?

Eric Dockett (author) from United states of america on December 04, 2018:

@FW Fishman - When you test your h2o what readings exercise you lot become?

FW Fishman on December 02, 2018:

I have a 100 gal. freshwater aquarium. I take performed iii fractional water changes in as many weeks and vacuumed the gravel. My water keeps turning white, cloudy. I am frustrated because I am doing what everyone says to practise but it just keeps getting worse. My tank is non over stocked, I accept an under gravel filter with two powerheads and an HOB filter. I do 25% h2o changes and add the necessary bacteria and startup fluids. What am I doing wrong?

Eric Dockett (author) from USA on November 23, 2018:

@vallamuthu - I have never fifty-fifty considered adding those things to a tank, so I can't even gauge if they are appropriate or non. Have you seen other aquarium owners try this? I would judge the debris and fine particles in the lake soil and compost are responsible for your cloudy water. Information technology may merely demand to settle.

No uncertainty you lot take added a lot of nutrients to your tank that will help plants abound, only when y'all accept soil from nature you are potentially adding a lot of other things too, such as pesticides, alive and expressionless organic material and harmful natural substances.

It sounds like a cool idea and I hope it works out.

vallamuthu on November 20, 2018:

Hi Eric Dockett,

I am having 200 liters tank for past half-dozen years. I constitute to abound live plants, so I have added normal lake soil and added little bit vermi compost. After that h2o inverse as cloudy. I have inverse the 75% h2o daily but it inverse every bit more cloudy.

Please give me your comments,

Thanks with Regards,

Vallamuthu Thou.

Eric Dockett (author) from USA on November twenty, 2018:

@Angela - Do you test your own water or did y'all have it done past a pet store? If the h2o is suddenly cloudy information technology seems like something had to change. Did yous add new fish? Did a fish die? Did you modify something in the room and so they are getting more low-cal? Perhaps overfeed a few days? A change to your water source?

Yous tin can try an activated carbon insert for your filter, just you really want to figure out why information technology is happening. Sometimes established tanks suffer from what is called "one-time tank syndrome" where problems slowly creep upwardly. You should meet any bug reflected in your testing though.

Angela Wells on November eighteen, 2018:

I have a cichlid tank a 3 foot one with about 20 cichlids in it they say also put that many in so they don't fight well I take had them ten yrs only all of a sudden the tank has gone a little cloudy not bad I had the h2o tested it's good so how tin can I articulate it it'due south never happened before would char Coal assist the fish are happy i don't understand what it could be I'd beloved some advice cheers

Ricky knuckles,sr on October thirty, 2018:

I got into fresh water aquariums virtually 3 yrs ago and trust you lot me I've fabricated every mistake one could make, if I haven't killed at least $400 in fish I haven't killed a 1. Because I done Piffling OR NO RESEARCH AT ALL and I paid for my mistakes. My firm burned downwardly December 2017 the only affair salvageable was only my 20 gal, after the burn down I got into African ciclids and a 75 gal tank, this time I done and re-washed enquiry, research, enquiry and more inquiry. In the last 9 months or then I've not killed or fifty-fifty gotten sick i fish I done my research

Eric Dockett (writer) from USA on September 20, 2018:

@Kenny - It's incommunicable for me to say without working on the tank. I'd merely be guessing. One affair I'd endeavour is reducing the h2o changes to every-other week to come across if that makes a difference. Keep testing your water. Otherwise, I propose learning every bit much as yous can, from this article and others, in society to go to the root of the problem. Good luck!

Kenny on September 14, 2018:

I've had my 30 gallon tank for 5 months. It has been perfect the whole time. I do regular water changes most 30% once a week. I've been testing my water and everything is perfect right where it should. I feed my fish in one case a day. This past week my water has been cloudy and I cannot get information technology to articulate upwardly. What else could it be and how can I set this

Eric Dockett (author) from USA on September ten, 2018:

@Cheryl - The only matter I can say is endeavour to pin down what is unlike with this tank compared to the others. Location, perchance? Too much sunlight? Plants/no plants? H2o change frequency? Are you using the same water source for all tanks? It'south tough to guess. I wouldn't tear down the tank until y'all've exhausted every possibility though, unless you tin can easily rehome your fish into your other tanks and just don't want the hassle anymore.

Good luck getting to the bottom of it!

Cheryl Rife on September 08, 2018:

Constant cloudy tank h2o. Tried near everything. Water tested skilful after cycling. A chip low on PH for Sail Fin Mollies but apply PH up with water changes. I am thinking I practise to many. Almost every other day I vac and do xx% change. Not over stocked, not over fed.

yet practice have black hair algae Using EF but does non impale all of it. Took out some things and ran them in hot h2o but this stuff is resentless. Put in extra filter pad this morning time simply and then far it is still the aforementioned. Accept Octo. cats and I call back it is to much for them to eat. Don't know what to practise next except take down entire tank, Merely practice not want to go threw this again. Any suggestions? The tank is a few months old. Have 6 tanks and this is the merely bad 1.

Eric Dockett (author) from USA on Baronial 29, 2018:

@Lizz - I'm thinking you lot are seeing a bacterial bloom in the 10g after water change. You already seem to take a handle on your feeding, and so you may want to vacuum the gravel every time you lot change the water if you don't already. I also doubtable your tank never fully cycled before you started calculation fish. Y'all can use a freshwater exam kit to measure your water parameters earlier and later on a water modify and it should give a skillful idea of exactly what is going on. Good luck!

Lizz on August 28, 2018:

I accept a 10 gal tank, with merely i guppy and 1 snail and 1-2 days afterward a partial water changes my tank turns cloudy. I let it bicycle virtually a month before calculation fish and it has done this since the fish were added about 8 months ago. I feed virtually a small pinch every 2 days and simply do partial h2o changes most one-two times a calendar month. I take a separate v gal tank with 1 goldfish and the h2o stays crystal articulate all the time. What am I doing wrong?

Eric Dockett (author) from U.s.a. on April 06, 2018:

@nancy - Have you tested your water using a freshwater test kit? Knowing your h2o parameters is the first footstep to figuring out what could be wrong.

nancy on April 04, 2018:

I have a 37 gallon tank for 8 months . Since day one as always had a white cloud look to information technology. I accept tried bottle water and out of the faucet. Never changes.even went and so far as to alter everything in tank including gravel. Same trouble immediately. Could led lights have anything to practise with information technology. I'm ready to pack information technology upwards. Please help.

Nicole tomlin on March 15, 2018:

We have a cloudy tank recently all was cleaned filter.. emptied some of the water and replaced... cleaned objects in the tank.. we don't accept a lot of fish for the large size of the Tank

It started out very clear but final few days gone cloudy!

Eric Dockett (writer) from USA on March 08, 2018:

@Virginia - Endeavour skipping the claret worms for a while and come across if that helps.

virginia feagin on March 07, 2018:

When I did a 2nd water modify it got cloudy, I thought it would clear up only information technology hasn't. I have a 29 gallon tank and have 11 fish. I give them a pinch of food around 10 in the morn. And give them a pinch of claret worms at vi at nighttime.

Eric Dockett (author) from Us on December 26, 2017:

@Laur - I guess it is possible the tank is still cycling and you accept a large bacterial bloom, though h2o conditioner shouldn't make your h2o cloudy under normal circumstances. Are you testing your h2o? You lot can either give it a few days and see if it clears upwardly, or since you have no fish you can replace the water and start over.

Laur on December 24, 2017:

I have a new aquarium and the h2o is cloudy. No fish...yet. i used a solution...Easy balance and I think that is the cause. What do you think?

Kelly on November 24, 2017:

This was the most helpful, detailed info out at that place..very good for new fish tank owners:) Thank you and so much!!!

Eric Dockett (author) from The states on Nov xv, 2017:

Keep trying unlike solutions, Fran. Something is off if the water is constantly cloudy. When you test your water does everything seem okay?

Fran on November 14, 2017:

I take a 20 gal. fish tank-i Oscar did all you said, still cloudy, very frustrating

Eric Dockett (writer) from U.s. on August 14, 2017:

@Cathy: Do you defrost the bloodworms in tank water and rinse them before calculation? In that location is a lot in those cubes, and while the fish may eat all the worms the extra droppings can add up over fourth dimension. You lot may also try skipping the bloodworms birthday for a bit and see if it helps. Good luck!

Cathy on August 12, 2017:

I accept had a 75 gal tank for vi months. It has been clear for nigh 1 week. So frustrated. All levels are good. Not overstocked. Not sure if I'grand over feeding. Have 1 leaf fish, 2 Bala sharks (6 inches), 2 roselines, 2 mollies. I feed twice a day ii cubes of bloodworms, tiny pinch of flakes, small cocktail shrimp for the leaf fish, that's all he wants to swallow

Eric Dockett (author) from USA on July 31, 2017:

@Nancy: I'm non sure what advice I can give aside from everything I have written in this article.

Nancy Morris on July 29, 2017:

Take Black Molly's and have a real problem with cloudy h2o- x gallon tank, have done everything, but even after changing the water, the cloudiness returns. Assist!!!!

Eric Dockett (author) from USA on July 17, 2017:

Hi Ballad. It doesn't seem soft water in itself should cause the cloudy tank issue. You mention using over-the-counter additives weekly. How oft are you doing h2o changes? If you are doing them weekly, peculiarly if you are vacuuming the gravel each time, I'chiliad wondering if you'd accept some luck if you backed off to every-other week or fifty-fifty monthly. If you are decimating the microbe colonies in your tank each week they may not be recovering enough to keep up with the waste matter processing. Expert luck!

Carol andress on July fourteen, 2017:

We have 7 fish in a lx gallon tank; 2 tetras and 5 of the glo fish. After several days of a make clean tank, the water starts turning cloudy. We practise all of your suggestions on cleaning, and we add algae fix, AcuClear and Prime number to the tank weekly. We have soft water. Could the soft water exist causing the problem?

Veronica Hazell on March 31, 2017:

this has been reassuring as it this is the first time this has happened it coincided with high nitrates as well though i take sorted that.

I accept been vacuuming daily this week to effort and clear up accumulated mess in substrate, some backlog fish evicted to friends etc water change for later.

will now attempt and address over feeding.

many cheers

Arthur on March 23, 2017:

Authentic and very helpful. The usual suspects and proper remedies abound. Cheers!

Louise on Jan 31, 2017:

I accept 4 parrot fish, 2 bluish arcua and ii kissing guarumi. Tank and heater is 2nd manus. Water is always cloudy and the heater goes way loftier

Eric Dockett (writer) from USA on January 28, 2017:

@ Chloe: Your tank may have turned cloudy for any of the reasons listed in this article. Without more than info it is impossible for me to say. I tin can tell y'all that goldfish should be kept separately and not with tropical fish.

Chloe Louise baggaley on January 25, 2017:

We have three goldfish and 2 loach and after 2 days the water turns cloudy.

Kevin Goodwin on August fourteen, 2015:

As long as you accept proper care of your tank and test the water and not overfeed or crowd your tank yous should exist good.

Pollyanna Jones from United Kingdom on August 14, 2015:

This is a really helpful guide. It's all ups and downs and it has gone a little flake cloudy at times! We bought our first aquarium last month and are trying to become the levels correct before we put fish in.