Cycling with Plants?

[Santiago]

Lady Hobbs wrote: --------------------------------------------------------------------------------

You have finished cycling your tank either by using the fishless cycle or have used fish. Even better, you have planted your tank with live plants and no cycling was necessary at all. If you plant your tank heavily and stock with a sensible amount of fish to start, the plants will eat up the toxins produced.

I can just add the plants and then the fish and all will be well? Advice please.

Thanks!

[rich311k]

You do that if you start with lots of plants and very few fish. You them let the tank catch up slowly to the fish load. You would still need to test and might find yourself still having to do a water change or two.

[JuliaC]

Theoretically that should work, and there are people for whom it did work.
However, here's my personal recent experience: I accidentally got 4 pygmy cories and I tried to do a "silent cycle" by putting them in a new 10g tank with a lot of plants (6 bunches of brazilian pennywort, about 30 stalks total, plus a medium-size java fern). I also gave them a filter that had been running in an established tank for about a week, plus I put a baggie with some substrate from that established tank into the filter. So all in all, I was pretty sure I'd avoid ammonia and nitrites. Especially considering that 4 tiny pygmy cories are not much of a bioload.
But I still got a cycle going. It was a much gentler one: neither ammonia nor nitrites ever got above 0.25 ppm with once a day 50% water changes. And it was a short one: it took only one week to get them to zero. But still that was a cycle.
So yeah, you can try that route, but you can't rely on it. So be sure to keep the bioload very low, test the water frequently and be very diligent with water changes.

[Sasquatch]

The "trick" with starting with plants is to have plants that are growing rapidly. Often when you introduce new plants, there is a certain acclimation period for the plants when they grow very slowly or not at all. If they're not growing, they aren't absorbing nitrogen (ammonia/nitri/ate) and so you'll still get a buildup in the tank.

[funkman262]

Sasquatch is right. Whenever someone tries this method, it's recommended to start with a lot of fast growing plants like hornwort and then eventually add in the slower growing plants.