Fed both tanks last night a 9:40pm and everything was fine. Came home from church this am and the 300 looked slightly cloudy so I walked up to it and discovered most fish were dead or dying. The ritteri was curled up quite a bit and clearly not happy. BTA's were shrunken but not completely withdrawn. Some inverts seem fine but a couple of red hitchhiker crabs were dead. Snails seem affected but not dead. Elegance and frog spawn very shrunken. SPS seem ok color-wise but not much PE.
We have a ground probe in the tank so I don't think stray voltage. Temp has been consistent at 78 degrees. Can't rule out biological or chemical contamination but also can't determine a source. I was gone most of yesterday so didn't even have my hands in the tank which is the only source of introduction I can think of and I am very careful around the tanks (and the other tank serves as a control group and is fine today).
Biggest issue is, I can't figure out what is wrong. Parameters are:
- Alk 9.3
- CA 480
- Mag - 1300-ish
- PH - 8.0
- Nitrates < 5
We dose CA, MG, vinegar and all reservoir levels look right so it doesn't see as if the doser freaked out. I feed both tanks the same food at same time and other tank is fine so food doesn't seem to be an issue.
The purple tang was one of the last to succumb but he seemed fine when I got home except he was gradually losing color in his dorsal fine. He died about an hour after discovering it.
About 7 fish are still alive - mostly smaller ones - 3 bangaii's, 2 clowns mandarin (although he looks quite sluggish so might not make it.
Dead: 11" male naso, 7" PBT, 6" gold spot rabbit, 6 lyertail anthias, 1 cardinal, and I'm sure I'm missing some. A couple of wrasses are MIA but I suspect dead in rocks.
I just finished a 55 gallon water change and have 75 gallons more mixing so will do another one and RODI is running so I can do another change late tonight.
Any idea what might cause this? A friend suggested bacterial bloom which might have created oxygen deprivation but PH is fine so that seems odd.
I have not changed anything, have not had any kids visit that might have "spiked" the tank with something.
Any ideas or hypothesis to check into would be welcome. At a complete loss as to what it might be. TIA.
We have a ground probe in the tank so I don't think stray voltage. Temp has been consistent at 78 degrees. Can't rule out biological or chemical contamination but also can't determine a source. I was gone most of yesterday so didn't even have my hands in the tank which is the only source of introduction I can think of and I am very careful around the tanks (and the other tank serves as a control group and is fine today).
Biggest issue is, I can't figure out what is wrong. Parameters are:
- Alk 9.3
- CA 480
- Mag - 1300-ish
- PH - 8.0
- Nitrates < 5
We dose CA, MG, vinegar and all reservoir levels look right so it doesn't see as if the doser freaked out. I feed both tanks the same food at same time and other tank is fine so food doesn't seem to be an issue.
The purple tang was one of the last to succumb but he seemed fine when I got home except he was gradually losing color in his dorsal fine. He died about an hour after discovering it.
About 7 fish are still alive - mostly smaller ones - 3 bangaii's, 2 clowns mandarin (although he looks quite sluggish so might not make it.
Dead: 11" male naso, 7" PBT, 6" gold spot rabbit, 6 lyertail anthias, 1 cardinal, and I'm sure I'm missing some. A couple of wrasses are MIA but I suspect dead in rocks.
I just finished a 55 gallon water change and have 75 gallons more mixing so will do another one and RODI is running so I can do another change late tonight.
Any idea what might cause this? A friend suggested bacterial bloom which might have created oxygen deprivation but PH is fine so that seems odd.
I have not changed anything, have not had any kids visit that might have "spiked" the tank with something.
Any ideas or hypothesis to check into would be welcome. At a complete loss as to what it might be. TIA.