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the cycle of a 20gallon tank

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Fish Fanatic
Mar 14, 2003
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Orlando, Florida
I have the whole idea down on how to cycle a tank, but i was wondering how long it would take to cycle my 20 gallon under the following conditions,

this is what I started with,

I started the tank up last sunday (3-30-03), so its been a little over 4 days.

On monday I added some flake food to decompose and get the bacteria started.

other than that I havnt touched the tank.

I also have a small heater that really cant keep up with the tank, I believe it was meant for a 10 gallon

I have an Aqua-Tech Power filter on it (Model 30-60) which i hear is equivalent to a Penguin 330 without the bio-wheel.. That means 330gph... so I guess that means im turning the water over about 16times an hour.. lol.. I didnt even realize that till I started this post

ok, I dont have a testing kit yet, so I dont really know what the water is doing.

Also it isnt getting any light, should I be letting some sunlight hit the tank to help?


The decomposing food trick could work, or you can get some pure ammonia, or as an alternative, a few small hardy fish (most people use danios) to really set off the cycle. If you have no tanks already running, see if you can get some "used" filter media or gravel from the LFS or from some other established tank (has to be kept wet) and add to your tank - this will help introduce the bacteria you need for the cycle and will speed things up a lot.
Positioning the heater where there is a lot of water current (like at the filter outlet) would allow it to heat the water up more efficiently :D
I don't think sunlight does much for the good bacteria...

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