Originally Posted by Tracy Bird
I'm very confused by this information, but I very much trust the source...
Aren't my trites and trates too strong to add fish?
Or are you suggesting a water change to remove the trites/trates?
It was my understanding you should not conduct water changes on fishless cycles and wait until Ammonia, Nitrites and Nitrates are at 0.0 before adding fish. By doing so it's an indication that the bacteria system is fully in place and is established.
No real changes to my parameters but I'm patient as I understand the trites/trates can take longer to drop than the ammonia.
Thank you - TB
There are two rather different methods of "cycling" a new tank. First with plants.
Live plants need nitrogen, and aquatic plants prefer ammonium as their source of nitrogen. Fish and bacteria [different bacteria from the nitrifying bacteria] produce ammonia, and live plants grab it fast. In acidic water the ammonia changes to ammonium automatically, and in basic water plants have the ability to change ammonia to ammonium. They use a lot of it. In a new setup with sufficient plants and some reasonably fast-growing plants [fast growth means more ammonia is needed and assimilated] and just a few fish, the plants will easily assimilate the ammonia from the fish (and later the bacteria too). As there is no secondary phase here, i.e., no nitrite is being produced when the ammonia/ammonium is taken up by the plants, there is basically no "cycle" issue.
Now, some ammonia will still get taken up by nitrosomonas bacteria, but it will be very little by comparison. And our test kits will normally not detect ammonia or nitrite in a well-planted tank. Thus, there is no harm to the fish. That's how it works normally. I have set up dozen of new tanks, always with live plants, and never had cycling issues and I add fish on day one.
Now to your case: As you have been adding ammonia to the tank, I would do water changes to get rid of it. Once it is zero, I would add a few small fish. The plants will assimilate the ammonia/ammonium from the fish.
Without live plants, one must deal with rising ammonia and then nitrites, both of which are toxic to fish (and plants for that matter). You can read more on this in my article on bacteria: Bacteria in the Freshwater Aquarium