Planted tanks = no cycling

[gunk]

Okay so I need to get some pregnant fish away from more aggressive fish who will eat the fry. I have a 10g with a makeshift sponge filter that I haven't had time to set up.

If I set it up as a planted tank and let the filter run for like a day, will it be safe to add the fish?

[Ellen4God]

I'd be a little hesitant in doing that. I guess you can give it a shot to see if your levels turn out okay like that.

[kaoticice]

I wouldn't recommend that method, its very risky. Even if you set-up a heavily planted tank, plants will still need the right condition before it can start balancing out the tank. I'll give it at least 4-7 days at least.
Some advices for quick cycling;
- add water from the original tank. Not only you'll get the same consistent water chemistry but you'll also seed beneficial bacteria to the new tank
- Adding mature filter sponge/medium including gravels.
- If you have plants from ur original tank, those would also help the cycle the tank.

[PUNISHER VETTE]

I'm going to go with no... Although plants will use a little ammonia they mainly take up nitrates which you'd need bacteria to process the ammonia to nitrites to nitrates.

I might even be wrong on that in that they might like ammonia more then nitrates but the ammonia is dangerous to fish so you don't fertilize for that.

Anyway a newly planted tank isn't going to have very good growth and there is already going to be enough nutrients for them to not need to take up much of the ammonia.

But thats just what i think. Go and buy some biospira or something of the like if needed. That or get a clear hang on divider for the fish to stay in while still being in the same tank.

[Anomaly]

As mentioned earlier, seed your tank using gravel and/or filter media from an established tank. That will help tremendously. If you have a local LFS that sells Bio-Spira, go buy it and add it to the tank when you add the fish.

That method works really well, but you'll still need to monitor your water parameters daily.

[Lady Hobbs]

Big tank I'd say yes. Small tanks will still get toxic levels.

[Mvjnz]

I don't see how you'd get away with not cycling just because it has plants in it. My tanks have heaps of fast growing plants in them, but they still needed cycling and when the power was out and the filter stopped working, the water went bad, despite the plants.

Btw, water does have any beneficial bacteria in it. The bacteria are in the substrate and filter, so using tank water will do nothing, except add nitrates to the water.

[ILuvMyGoldBarb]

Devil's advocate here.

Silent cycling a tank is an excellent way to get things going. It works something like this. A tank get's fully planted from the very beginning and proper ferts are added minus nitrate. Then, a smaller bioload is introduced to the tank immediately. Plants take up nitrogen in 2 forms, one of those is NH3/NH4. If enough plants are planted and the bioload added is not too high, then the plants will take in the NH3/NH4 as fast as it is produced, thus the NO2 stage is never really reached to detectable levels. This does work, I've done it and I know many other people who have done it as well. You just need to be sure to add a lot of plants in the very beginning. Tank size is somewhat irrelevant, the main concern here is bioload, of course that is linked to tank size, but that is the key, keep the bioload down and it does work very well.

[KingFisher]

Devil's advocate here.

Silent cycling a tank is an excellent way to get things going. It works something like this. A tank get's fully planted from the very beginning and proper ferts are added minus nitrate. Then, a smaller bioload is introduced to the tank immediately. Plants take up nitrogen in 2 forms, one of those is NH3/NH4. If enough plants are planted and the bioload added is not too high, then the plants will take in the NH3/NH4 as fast as it is produced, this the NO2 stage is never really reached to detectable levels. This does work, I've done it and I know many other people who have done it as well. You just need to be sure to add a lot of plants in the very beginning. Tank size is somewhat irrelevant, the main concern here is bioload, of course that is linked to tank size, but that is the key, keep the bioload down and it does work very well.

That's exactly how I did my 29 gallon tank this past time and I never had a bad reading the whole time. It is very important to add the fish slowly over a period of weeks or a month to let the bacteria get established in the filter.

[Evil Slimy]

+1 to what ILuvMyGoldBarb said, assuming you plant heavily and with fast growing plants.