How to Clean a Dirty Fish Tank

Introduction: How to Clean a Dirty Fish Tank

How to Clean a fish tank

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Step 1: Step 1

Take the plants out of your fish tank. This will make it easier to clean the tank and the plants. 

Step 2: Step 2

After you have the plants out use the cyphon to vacuum out the water and the algae out of the rocks. Make sure as the water lowers you turn off the pump. Leaving the pump on with no water could ruin it.

Step 3: Step 3

After you finish "vacuuming" the water. Use a brush, or something to scrap the algae of the sides of the tank. Move the rocks out of the way to make it easier to scrub the sides. 

Step 4: Step 4

Take out the pump to clean it. 

Step 5: Step 5

Clean your filter. Use a toothbrush, that no one uses, to scrub off some of the algae in it. You wont be able to get all of it off.

Step 6:

Your filter should not look like this! Make sure you replace them often. 

Step 7:

Your filter should look like this after you replace the old stuff.

Step 8: Step 6

Clean the plants. You can do this by place the plant between your hand and rubbing it really fast under warm water. Most of the noticeable algae should come off. 

Step 9: Step 7

Pour some water back into the tank. Then put the filter/pump back in the tank. Fill it up with water before plugging it back in. 

Step 10: Step 8

Now add your plants back in. 

Step 11: Step 9

Now finsih filling up your tank with water.

Step 12: Your Tank Is Now Clean! YAY!!!!

Let the water sit for awhile. Then it will turn clearer than before. 

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    3 Discussions


    6 years ago on Introduction

    Seriously and facing the "be nice policy" of Instructables, but this is all, errr..., "not that right".

    If your tank somehow manages to look like that, some or several things must have gone kinda wrong.

    See the photos of my tanks, that´s a (e.g. one of many) way(s) fishtanks could/should look like.
    And I -seriously- don´t have to "clean" them at all.
    They work pretty autonomous, despite lighting, watercirculation and feeding.

    All I do is:
    - rinsing the filter materials half a year or even less, since they never really clog up
    - exchanging/refilling some water once in a while
    - trimming (and selling ;) ) the plants if they grow too much

    I´m planning on publishing an Instructable regarding almost maintenance-free (freshwater) fishtanks since there are so many misleading 'íbles out there.
    Will tell you when it´s published :)

    Rules of thumb:
    - Dont´t clean your fishtank like it´s a piece of dishes! It is not, it´s an ecosystem. If you do so, it means hard times for its residents, if they survive such an intervention at all.
    - Add LIVE plants! (lots of them and at best some weeks before putting live fish in your tank).
    - Maximize the area in which bacteria can do its job, when you got only a small filter/pump, you can add a piece of really RAW filter mat right in front of the intake of the pump. This will prevent clogging since big parts of "waste", aka dead leaves or even leftovers of dead fish can not get into the pump/filter. They will decompose "there" and also provide a nice meal to your fishes, snails and microfauna. That´s not gross, that´s nature. Fish eat dead fish and/or dead plants and snails do alike. Smaller leftovers aka fish and snail poop can still get through that barrier and will be processed inside the "filter".
    - Think of your filter/pump as a bioreactor or catalytic converter and not a "filter". Its job is NOT to filter out particles and gunk and get cleaned/rid of them, its job is to "metabolize" them and turn all of it into clean water, plant fertilizer and much more useful and healthy things for your fishes and plants.
    - Bacteria and "gunk" are your friend(s), bacteria clean the water and the gunk is their home. So make sure there is some nice and cozy place for them to settle. Assuming that no one likes a pile of gunk right behind the front glass, give it/them some space in the back of your tank or in a generous construed filter area.
    - Feed responsible, e.g. only the amount your fishes eat within a few minutes without leftovers. The leftovers will feed the algae and not the fish. The fish will only pick floating food, not the flakes on the ground. Despite you own some catfishes or sth. alike which pick up food from the ground.
    - Recruit some assistants. Snails will keep your tank and plants free of algae and leftover food (but can turn into a pest if you [still] feed too much).
    - Don´t clean/sterilize/replace the filter materials! Just rinse them gently under handwarm water and only replace them if they´re almost decomposed, which only should happen after years, not weeks.

    I´m keeping fishes of all kinds for almost 25 years now, I´m just suggesting not offending.




    6 years ago on Introduction

    As the co-owner of an aquarium service company, I have to say that you should definitely scrub the algae from the glass before you siphon, letting it settle first. I also completely agree with blackishsheep about the filter. If your lighting is strong enough, I suggest getting live plants to help absorb the nitrates that your algae are thriving on. Also make sure that your are not over-feeding fish. We recommend weekly small water changes of 10-20%, instead of less frequent larger ones. You have a single-celled, free-floating algae more commonly called green water. Keep your lights off for a week or so and feed your fish sparingly (but don't starve them). This should starve out the algae (unable to photosynthesize without light) after a nice water change. If your tank is in direct light from a nearby window, you may want to limit the amount of natural sun hitting the tank. Gradual increase the lighting over a couple of weeks. Get a timer for you light before getting live plants. Keep the timer on no more than 8-12 hours per day. (If you like your tank lit at night, be sure to limit the sun light from windows during the day). If you have goldfish, you will need to keep up on water quality and filter maintenance more often than with other species, as goldfish put off more waste matter and will eat much more than they need. I hope this helps. I attached an image of our oldest service of 15 years.


    6 years ago on Step 5

    It'sbetter to wash your filter out by squidging the sponge over and over in a bucket of fish tank water. This way you get rid of the gunk but keep the bacteria alive. The bacteria helps keep the tank healthy by breaking down the organic leftovers etc etc Washing it in tap water kills the good bacteria and you'll have to start cycling your tank all over again, and bacteria bloom can be deadly to fish until it settles.