Ammonia & high nitrates??

Hi all,

I fear my cycle may have crashed or something. We had a power outage two days ago and were without power for about 7 hours. I got home and saw that the power was off and nobody else was home to tell me the power went off so my filter media probably suffered. I have an Aquaclear HOB filter and there was still some residual water in the filter "box" so the main foam sponge was still underwater. I had completely cycled my new 30 gallon breeder tank with 0 ammonia, 0 nitrites, and a little under 40 nitrates two weeks ago and my adult wildtype axolotl had been living there for about a week.

Yesterday I tested the water and I had about 1.5ppm ammonia, 0 nitrite, and 80ppm nitrate. I freaked out and did about a 30% water change. Today the ammonia reading was a little closer to 1ppm and the nitrate was still very high, still around 80ppm.

Have I crashed my cycle? Any tips? Should I keep doing daily water changes and see what happens?

1 ppm of ammonia is still too high; you want it to be under .5 max at any point in time (i.e. no more than that just prior to your next water change), so you'll want it much lower than that right after your water change. I'd probably aim for .25 max myself. You could do lower volume water changes more often, for instance. Likewise, nitrates should be under 20.

If the tank was cycled completely, it may just be dented a bit, versus crashed completely. Did you do a fishless cycle? Things do change once you put your axie in the tank, and as it was only a week, the cycle might never have adjusted completely. Cleaning up waste and extra food right away will help.

However, you'll only know what the state is by doing the water changes and testing.

Likewise, nitrates should be under 20.

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Nitrates should be under 40. Around 20 is good. The cycle can get off balance even if you just let your nitrates get too high so I'd suggest doing a massive water change to bring the nitrates down to about 20. Then keep testing the water every day to see if ammonia starts building up again.

This summer during a heat wave I tried to get my plants growing better while my axies were in their temporary tanks in my basement away from the heat. I kept dosing some ammonia in my big tank and didn't do many water changes, mostly just added some water when it had evaporated. So I got my nitrates up to something very high, can't remember exactly, and suddenly I started seeing also ammonia and nitrite in the tank. Once I did a huge water change and the nitrates were back to normal there was no more ammonia or nitrite either and hasn't been since.

Thank you both! Would getting an additional filter help? I was thinking of getting a sponge filter to put in the other corner of my 30 gallon breeder tank since the HOB filter is on the left corner. I know that adding Ammo Lock and other things are just a temporary fix so I want to make sure I have enough biological filtration to keep the ammonia levels in check.

Well, biological filtration needs to be grown over time. If your current filter is sized sufficiently for your tank, adding another filter won't help to really with the current situation; just do water changes until things stabilize.

If you got a second filter, over time each would end up being able to handle only half of the biological load for your tank, in theory. Which isn't necessarily a bad thing; if less bacteria are feeding on what's stagnant in the HOB, the contents will last longer.

However, if you're concerned about long power outages, a sponge filter with a battery operated backup air pump might be an inexpensive solution. I've never seen a battery backup powered air pump that people have exactly raved over in reviews, so I haven't gotten one myself. Even without the battery backup, I'd wager that the sponge would do more through osmosis due to being in the tank versus an isolated HOB filter (or a canister for that matter).

A UPS system for the HOB would probably be more expensive.