I have a discus tank, or what used to be a discus tank. It is a 28 gal bowfront. I run a bare bottom. In the tank is a 8" x 8" x 3" piece of driftwood. Placed in and around of the driftwood are a few sword plants, as well as 4-5 other small plants. I run an eheim 2217 canister, 2 Topfin 10 HOB filters, and 1 Whisper 20 in tank filter (this filter is fully submerged with filter fiber as media). In my canister I have a course pad, prefilter clay rings, medium pad, filter fiber, a fine pad, one box worth of biomax, and another fine filter pad layered bottom to top respectively. I also have a Whisper 40 air pump with 12" air stone and 2 heaters that keep temp around 84 degrees.
Water parameters as of 5-6 days ago:
pH: 6.6
NH3: 0
NO2: 0
NO3: 5
Water parameters as of today:
pH: 6.6
NH3: .5
NO2: 0
NO3: 0
So it would certainly seem as if I restarted my cycle somehow. During the last 5-6 days (when I personally last tested my water) I have done a couple 75% water changes. I have a bare bottom so I always make sure to get everything off the bottom. I feed fish in smaller amounts several times a day.
Stocked in the tank I had 2 adults on the stunted side and one juvenile 2" long.
I moved one of the adults to a friends house for breeding purposes night before last. When I did I drained some water out into the transport bucket. This lowered the water level below the point that the two Topfin 10 HOB scould operate so I switched them off.
This is where I feel I may have made an error. I had a packed schedule yesterday and didn't end up toping off the tank enough to where I could turn the HOB filters on again. The other filters and air stone were still running.
When I woke up this morning the little discus was dead. I did tests but really didn't even think to check the ammonia, cocky on my part. I found out at my LFS when I went for hardness test specifically, and anything else they wanted to test.
When I got back my remaining discus was showing signs of ammonia poisoning. He is in an alternate tank now and is doing better but doesn't look out of the woods yet (I checked the ammonia in that tank before adding!).
So I have a few theories:
1) I usually keep up very frequent water changes every 2-3 days of at least 50% usually 60-70%. I already had very low nitrates indicating not much NH3 to go thru the nitrogen cycle in the first place. The last time I serviced my canister filter was approx 4-5 weeks ago and I am worried that I may have damaged my biomedia in the process (I'd rather not explain). So the canister may not have built up the necessary bacteria yet since the process supposively can take up to 6 weeks.
This coupled with an increased demand on the remaining Whisper 20 filter may have caused the ammonia spike. Due to my low nitrates I probably should have thinned my plants while ago. They had some, although not alot, of dying leaves that may have caused NH3 to rise quicker.
2) I changed my water too much. In theory if I do too many water changes and keep the water 'too clean' there may not be enough acculation or even presence of the necessary elements to keep the nitrogen cycle going and the system crashed.
3) Although I've had alot of success with canister filters, I may have too much faith in them to run even a 28 bowfront along with a Whisper 20. I may have just not had enough circulation even if I had bacterial colonies established in the media.
4) Probably most likely a comination of them previous 3.
Besides moving the fish out of the aquarium I have: topped off aquarium with R/O water usually reserved for my saltwater, restarted HOB filters, pruned plants and added additional biomedia from other tank (that has been historically disease free).
If you agree with any of my theories please let me know. Or if you have any additional theories or advice I'd like to hear from you as well. Thank you for your time!
Water parameters as of 5-6 days ago:
pH: 6.6
NH3: 0
NO2: 0
NO3: 5
Water parameters as of today:
pH: 6.6
NH3: .5
NO2: 0
NO3: 0
So it would certainly seem as if I restarted my cycle somehow. During the last 5-6 days (when I personally last tested my water) I have done a couple 75% water changes. I have a bare bottom so I always make sure to get everything off the bottom. I feed fish in smaller amounts several times a day.
Stocked in the tank I had 2 adults on the stunted side and one juvenile 2" long.
I moved one of the adults to a friends house for breeding purposes night before last. When I did I drained some water out into the transport bucket. This lowered the water level below the point that the two Topfin 10 HOB scould operate so I switched them off.
This is where I feel I may have made an error. I had a packed schedule yesterday and didn't end up toping off the tank enough to where I could turn the HOB filters on again. The other filters and air stone were still running.
When I woke up this morning the little discus was dead. I did tests but really didn't even think to check the ammonia, cocky on my part. I found out at my LFS when I went for hardness test specifically, and anything else they wanted to test.
When I got back my remaining discus was showing signs of ammonia poisoning. He is in an alternate tank now and is doing better but doesn't look out of the woods yet (I checked the ammonia in that tank before adding!).
So I have a few theories:
1) I usually keep up very frequent water changes every 2-3 days of at least 50% usually 60-70%. I already had very low nitrates indicating not much NH3 to go thru the nitrogen cycle in the first place. The last time I serviced my canister filter was approx 4-5 weeks ago and I am worried that I may have damaged my biomedia in the process (I'd rather not explain). So the canister may not have built up the necessary bacteria yet since the process supposively can take up to 6 weeks.
This coupled with an increased demand on the remaining Whisper 20 filter may have caused the ammonia spike. Due to my low nitrates I probably should have thinned my plants while ago. They had some, although not alot, of dying leaves that may have caused NH3 to rise quicker.
2) I changed my water too much. In theory if I do too many water changes and keep the water 'too clean' there may not be enough acculation or even presence of the necessary elements to keep the nitrogen cycle going and the system crashed.
3) Although I've had alot of success with canister filters, I may have too much faith in them to run even a 28 bowfront along with a Whisper 20. I may have just not had enough circulation even if I had bacterial colonies established in the media.
4) Probably most likely a comination of them previous 3.
Besides moving the fish out of the aquarium I have: topped off aquarium with R/O water usually reserved for my saltwater, restarted HOB filters, pruned plants and added additional biomedia from other tank (that has been historically disease free).
If you agree with any of my theories please let me know. Or if you have any additional theories or advice I'd like to hear from you as well. Thank you for your time!
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