View Full Version : I killed my fishless cycle!!!!

03-02-2009, 05:36 PM
Was about 5 wks. into my fishless cycle, everything was looking good, 0ppm ammonia daily after dosing the night before with ammonia, nitrites finally spiked and dropped to zero. Did 50% wc, waited two days GRADUALLY dropping the water temp for goldfish. Water tests looked fine the night before so I went the next day after work and got two black moors, just for the heck of it I tested the water JUST after adding them, 4ppm ammonia and .50ppm Nitrites, WTF!!

03-02-2009, 06:47 PM
Goldfish are heavy bioload fish. Most probably, what happened was that your fish overwhelmed the established biofilter. Not to worry, though. Your tank already has the needed bacteria and the colonies will grow to handle that bioload (provided the filter/tank/sustrate are enough for them). While this happens, your water will be a bit cloudy, but that will go away. Give it a few days...

03-02-2009, 07:26 PM
No, I tested for ammoina and nitrites within 5 minutes of adding the fish!! I would expect them to put a dent in the cycle a few days after adding them, but this was within minutes. The test from the day before (no fish) was perfect!! All I can fiqure is a 12hr. drop in temps of 5 deg. or so killed my bacteria?

03-02-2009, 07:32 PM
What temp is the tank at now? You didn't forget the dechlorinator, or wash the media in tap water?

03-02-2009, 07:33 PM
how are the fish? check your readiings again and if they are that high do some major water changes.. i see this so often and most of the time its just a bad read on the test checking it again almost always comes up ok... any time you get a sudden change like that retest the tank

03-02-2009, 07:50 PM
After levels tested okay I siphoned 50% of the water, didn't mess with the gravel or filter, added Tetra declor with filter off and refilled via buckets. Turned filter back on after a half hr so the declor had time to work before going through the filter. The water is now at 68F was at 85F. I didn't want to shock my bacteria, so I stagged the temp drop over two days by turning down the heater a few clicks at a time. Levels are still high for both ammonia and nitrites. Added Ammo-Lock, going to do a 40% wc tonight.

03-02-2009, 08:36 PM
Hmmm, did you dump the water from the bag the fish were in, into your tank also?

03-02-2009, 08:49 PM
Bailed about half of it out with a cup and gradually replaced it with my water while floating the bag.

Lady Hobbs
03-02-2009, 09:57 PM
I believe when you waited for two days, your bacteria died. That's why it's so important that ammonia or fish be added to the tank immediately when the tank is done cycling. Even if you had added a couple spoonfuls of ammonia, it would have been sufficient to keep the bacteria "fed."

All you can do now if watch the water closely and hopefully it will cycle again without taking very long. Why your ammonia would jump back up to 4 right after adding your fish....... I have no clue.

03-02-2009, 10:14 PM
I was 'feeding' my pet bacteria daily just enough ammonia to get it to 2ppm. Just did a 40% wc, test results were the same before the wc, 4ppm ammonia, about .25ppm nitrites. Nitrates are around 10ppm, were 40ppm before the big fishless wc.

03-02-2009, 10:18 PM
How are the fish doing? If they look fine, I wouldn't worry too much for now. Also, what type of tests do you have? strips or liquids?

03-02-2009, 10:19 PM
is your tapwater treated with chloramine? Your tests may be reading ammonium

03-03-2009, 12:03 AM
Did the filter dry out for those 30 minutes? My HOB filter siphons itself dry. If the filter dried out for those 30 minutes, the bacteria may have died. However, if you were feeding the bacteria while dropping the temps you should have enough left on the filter and surfaces in the tank to quickly recycle the tank.

03-03-2009, 01:06 PM
Using API master test kit, and a Top Fin 30-60 (Whisper) HOB filter, I'm pretty sure water stays in the wells by the media. The tank is in my living room and the Top Fin is noisy so it's getting replaced with a Penn-Plax Cascade canister soon.

03-03-2009, 01:24 PM
is your tapwater treated with chloramine? Your tests may be reading ammonium

Well, I pulled the water quality report for my county from the net, they use chlorine, but i did find it interesting they list .36ppm of Nitrates and Nitrates from the reserviour I use. Another reserviour in the cty. has 1.85 ppm of Nitrites and Nitrates. Max allowable by the state is 10ppm. In the column they say the source is from "fertilizer runoff, leaching from septic fields and erosion of natural deposits". Next year the source will be listed as "Ed's fish tank" :hmm3grin2orange:

03-05-2009, 01:41 PM
Update, things are looking better, ammonia dropped by half yesterday and nitrites to 0!! Guess the cycle is back on track.