Semi Newbie needs help with fishless cycle

Do you have access to established media?

Have you had your test results confirmed by a third party?

Other water parameters--KH, GH, pH? Unlikely to be stable at this point, but knowing your KH is important for fishless cycling.

Sounds like you got some bad advice along the way...

Part of what happened is that the ammonia concentration went so high that any bacterial was probably inhibited. The second stage bacteria, the nitrite-eaters, in particular seem to be inhibited by high levels of ammonia.

Looking at your data from May 24 on, it looks like things are progressing. You're getting nitrites, which is a very good sign. It can take a while for the nitrite eaters to get going, but if you keep ammonia below 5 ppm you should be OK. Do you know if you're getting any nitrates yet? If you do have nitrates (in excess of what your tap water contains), that would suggest that you have at least some nitrite eaters.

I would add only enough ammonia every day to get the concentration up to 4-5 ppm. You should nitrites continue to climb -- this can take a while -- but then they'll drop fairly suddenly. If you also start testing for nitrates, you'll get a stronger sense of how quickly the nitrite-eaters are growing.

Hang in there, you'll make it!

Jim

What we don't know that would probably be pretty important is KH and pH. There is a pretty strong body of evidence that shows fishless cycling to burn thru buffering (KH), which causes pH to drop. As pH drops to 6.0 or so, oxidization of ammonia slows and stops somewhere around 5. If you have soft water (low KH) it's very possible that you depleted KH and retarded the ammonia eaters (thus decreasing the amount of nitrite being produced).

This hypothesis doesn't explain why nitrite dropped staring around May 1, although it may be that the nitrite eaters were less affected by KH/pH conditions and consumed some of the available nitrite, which wasn't replaced because the ammonia eaters were slowing down.

This all hinges on the assumption that KH was depleted and pH dropped, so if you have any data on those from the cycle, that might shed some light on the situation.

Jim

Info source?

What directions are you following for this?

The info I've seen says to take the tank to 5ppm at the start, add ammonia daily to keep it at that point. When the first nitrites show up, drop the daily addition to half. Continue like that until done.

So, if you added 3 ml the first day, then the second day the tank measured 4ppm, you'd add 0.6 ml to take it back to 5ppm. A few days later you see 3ppm in the morning, so you add 1.2 ppm to take it back to 5ppm. Then you see nitrites, so cut to half and add 0.6 ml daily from then on.

But, I did a fishy cycle myself.

The different flucuations of amm. input is probably whats causing the weird read outs, and prolonged cycle. It's like when you add more fish, the bac has to compensate for the new source of amm. You added more then enough a few days and then a little less the next. Every time you add a fish to a tank or remove one, the bac. level changes to compensate for the loss or addition. In essence once the main cycle completes every addition or loss 're-cycles' the tank. It just takes less time and is less of a spike because there are already bac. there. It has to be stable for you to get accurate results in your test.

I prefer doing it with dead shrimp that way amm and rite spikes on it's own and all you have to do is watch and test.

Here's my advice. You don't have to do it this way but it's what I would do (using the adding amm. method).

I would just get rid of the water and start all over from scratch. You shouldn't have to rinse anything as it shouldn't be dirty. I would let it sit for a few of days while running the filter and what ever else you have. Then test everything as you have done. (ph, amm, rite, and rate)

Now depending on what these readings are you will know what to do. I would then add enough amm to get it to 5 ppm. Continue this until nitrites show up. Then as the earlier post suggested cut amm in half. The reason for this is because the bac. that established to take care of amm. has to have something to feed off of.

Once the nitrite kicks in the nitrates should soon follow, as this is a waste product of those bac. Once amm and nitrite are stable at 0 for a couple of days you should be ready for fish. If your nitrates read over 30 ppm at this time you should do a water change, if not, it's not really nessecary. Make sure you get fish in the tank sometime soon after this, or keep adding the amm. to feed the bac. or else the bacteria will start to die off.

Hopefully that made some sense.

by cutting back on the ammonia dosage won't some of the already established bacteria die since there will not be enough ammonia for all of the bacteria to feed on?