Help Ammonia Spike To Cycled Tank, Too Small A Bioload? Thoughts? (2 Deaths So Far)

WildType

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I'm having a pretty helpless feeling over here right now.

Tank is a 45 gal. It was cycling 4ppm per day. About 10 days ago I stocked 8 little 1 inch baby Synodontis lucipinnis. Yesterday I found a dead fish and another swimming at the surface.
Ammonia: 0.5, nitrite 0, nitrate 5 ppm. Nitrate is same as last week pre 30% water change. Sadly I didn't check it after to be sure it's still cycling.

I did a 60-70% WC and double dosed prime. The sick fish died. I counted 6 living fish so no dead ones left decomposing.
Today the ammonia again looks between 0.25 and 0.5. I decided to add half a bottle of TSS+ I had instead of water changing again because that didn't seem to help.
What do you think I should do? I withheld food yesterday and the fish appear slower moving but otherwise just fine. My only guess for causes is either the bioload is too small to maintain my cycle or a fish randomly died and spiked NH3.
 

MrBryan723

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Your bioload is too large too quick. Since you already have the BB I would just up water changes for a while to keep them under .25, catfish are a bit more sensitive to ammonia and nitrite than other species as a general rule.
 
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WildType

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I had always thought 4-5 ppm cycled per day supports a huge bioload. And then it was fine with no spikes for over a week.
Considering they were fasted yesterday would you feed today?

I'll do a big WC tomorrow if the bottled bacteria has no effect on the ammonia level.
 

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I would think that if your filter is processing 4ppm ammonia, I can handle 8 small fish.

did you test your tap water?

did you QT the new fish?

you can dose up to 5X Prime every 24-48hrs.
 

mattgirl

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How big a water change did you do after cycling and before adding fish? If you were cycling this tank by adding 4ppm ammonia each time and weren't doing water changes as the nitrates rose I have to think they were really high. The nitrate test will default back down to 5 when they go so high you can't get a reasonable number. The instructions don't say this but I have seen it happen time after time so I know it does happen.

when the nitrates get that high the bacteria slows down on processing the ammonia. I have to think that is why you are getting an ammonia reading now.

If this were my tank I would do several back to back 50% water changes. Test for nitrates after each water change to see where you are. Once you get them down to 20 or so you can then go to weekly water changes. At that point you just let your numbers be your guide as to how much water needs to be changed.

edited to add: I just thought of something else. Have you run the PH test? If for some reason it has dropped below 6.5 or so that could also be the problem. Ammonia turns to ammonium in a very low PH situation. The good news is ammonium isn't as harmful to the fish. The bad news, it isn't the best food for bacteria.
 
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WildType

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mattgirl said:
How big a water change did you do after cycling and before adding fish? If you were cycling this tank by adding 4ppm ammonia each time and weren't doing water changes as the nitrates rose I have to think they were really high. The nitrate test will default back down to 5 when they go so high you can't get a reasonable number. The instructions don't say this but I have seen it happen time after time so I know it does happen.

when the nitrates get that high the bacteria slows down on processing the ammonia. I have to think that is why you are getting an ammonia reading now.

If this were my tank I would do several back to back 50% water changes. Test for nitrates after each water change to see where you are. Once you get them down to 20 or so you can then go to weekly water changes. At that point you just let your numbers be your guide as to how much water needs to be changed.

edited to add: I just thought of something else. Have you run the PH test? If for some reason it has dropped below 6.5 or so that could also be the problem. Ammonia turns to ammonium in a very low PH situation. The good news is ammonium isn't as harmful to the fish. The bad news, it isn't the best food for bacteria.
I definitely did a 90+% water change before I added new fish to flush the nitrates so no worries there. My tap water is at about 8 with a high kH so I'm not worried about fluctuation.

Skavatar said:
I would think that if your filter is processing 4ppm ammonia, I can handle 8 small fish.

did you test your tap water?

did you QT the new fish?

you can dose up to 5X Prime every 24-48hrs.
After testing both twice it looks like my tap water has higher ammonia than my tank does. Tank is looking between 0 and .25 and tap looks between .5 and 1.0...
I didn't quarantine because these are my only fish in the tank. And only tank setup.
I'm holding off on dosing prime now because the TSS+ says not to dose both.
 

mattgirl

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WildType said:
I definitely did a 90+% water change before I added new fish to flush the nitrates so no worries there. My tap water is at about 8 with a high kH so I'm not worried about fluctuation.
Well shoot. I was hoping we had an answer as to why you are getting an ammonia reading in a cycled tank that should have any with the low bio-load you have added.

Since you cycled it with enough ammonia to build a big colony of bacteria you shouldn't have had a glitch once fish were added.
 
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mattgirl said:
Well shoot. I was hoping we had an answer as to why you are getting an ammonia reading in a cycled tank that should have any with the low bio-load you have added.

Since you cycled it with enough ammonia to build a big colony of bacteria you shouldn't have had a glitch once fish were added.
I thought I would update this thread with a possible reason for the ammonia spike. It appears one fish got into a tiny hole in a ceramic ornament, got stuck, and died. I think when I did a headcount I made a mistake counting one fish twice. I made another thread when I suspected a missing fish that has more details.

Thanks for your and everyone else's support!
 

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