Can you have too few fish?

[KyleBradley]

I was just wondering if it's possible to have too few fish to maintain a cycled tank? My 20-gallon hex now only has 3 small corydoras in it now.. Is that sufficient to maintain a cycle?

My thoughts are that the fish will produce what they will produce, and the bacteria will die off to whatever level is sustainable by those three fish. Is that accurate?

Thanks.

 

[1077]

You are correct. Bacteria develops in proportion to available food for it to feed on. Is why sudden addition of several fish at once ,can lead to ammonia and nitrite spikes.

 

[Lotus]

Three cories will be fine, but as 1077 says, avoid adding a lot of fish at once.

The bacteria colonies do indeed keep pace with the amount of ammonia produced by the inhabitants. Bacteria colonies will increase or die off depending on the bioload.

 

[KyleBradley]

Three cories will be fine, but as 1077 says, avoid adding a lot of fish at once.

The bacteria colonies do indeed keep pace with the amount of ammonia produced by the inhabitants. Bacteria colonies will increase or die off depending on the bioload.

Thanks.

I've been meaning to ask you a question because of your heavily planted tanks-is there ever enough plants in a tank where you don't need to do water changes? More specifically, I've read that ammonia is taken care of by the bacteria that converts it into nitrites, which is in turn taken care of by the bacteria that turns nitrites into nitrates and then water changes and plants are what get rid of nitrates..

Also, will my crayfish eat my plants? I could just google that, but while I've got you here.. *ALL*

 

[Lotus]

Well, the plants need the water changes, too. While the plants will use up ammonia, nitrites and nitrates, they also deplete minerals from the water. In addition, fish add other pollutants to the water, such as hormones, which we just have no way of measuring. The Walstad Method is a particular method some aquarists use that has water changes only once every six months or so, but it is under a specific set of parameters and tank set up configurations that just doesn't appeal to me.

Basically, my tanks are heavily planted, have good amounts of fish, and get a weekly water change.

Yes, crayfish will destroy your plants

 

[KyleBradley]

Do you use one of those faucet attachment deals that siphon the old and put in the new at the same time? If so, how do you deal with chlorine?

 

[tlkng1]

If you are filling directly from the tap, add the dechlorinator to the tank and then fill. Maintain a good mix of water, as in water movement, and the dechlorinator will interact with the incoming water flow.

 

[KyleBradley]

If you are filling directly from the tap, add the dechlorinator to the tank and then fill. Maintain a good mix of water, as in water movement, and the dechlorinator will interact with the incoming water flow.

I was wondering about that! So how much dechlorinator do you use? I have a 35-gallon tank, but I only change about 8-9 gallons at a time, and my Aqua-Safe says to use 1 teaspoon for 10 gallons.. Do I put enough in my tank for only 8-9 gallons?

I've been treating in the buckets before I dump it in, but I'd like to use one of those dual function hoses that drain and fill at the same time.

 

[Lotus]

Just put in the dechlorinator before you start to fill, and you're all set. If you overdose a little on the dechlorinator, it's not a big deal. If it's easier for you to add a teaspoon (rather than 9/10 of a teaspoon), it will be fine.