Rapid Fish Loss

[TinaM]

I originally posted this in the fish disease forum, but I think it probably belongs in this forum, since I do not have much experience!

I have had my tank up and running since October 2005.

46 gal. FOWLR
45-55 pnds live rock
live sand
CPR Protein Skimmer
maxi jet 1200 power head

temp 75-78
Nitrates 10
Nitrites 0
Amonia 0
PH 8.0

After the tanks cycling I added 2 damsels, lawnmower blenny, 2 feather dusters, 2 hermit crabs, all from a previous tank that I had for about a year.

about a month after that I added a tomato clown and a pair of percula clowns (who all got along well)

about a week after the perculas were added the smaller of the two died. A few days after that the larger one died. I read that sometimes this sort of thing happens with percula's. So I decided to wait about another month and purchased a royal gramma. I noticed that one of my damsels was aggressive towards this fish so I decided it was time to take him out. I had to take out 75% of the LR to catch him. I put the rock back in waited a few days and decided now would be a good time to add another fish, since territories have been disturbed and I got rid of the bully. i bought a yellow angel and a cleaner shrimp. About a week after I bought him he died. No apparent illness? A couple weeks after he dies my blenny died. I had him over a year and he ate very well?? I did notice right before he died he was hanging out in the return pipe of the protein skimmer. It is like he was trying to get some fresh water?? No apparent signs of illness for him either. Two days after the blenny died the royal gramma was dead! i then took the tomato clown out and my other domino damsel I decided to keep. These were the only two left. i put them in a QT and shortly after the clown died. Now I have the damsel left but he is VERY pale. And at times it looks like he is going to die. Very lethargic. My crabs are fine as well as the shrimp. The feather dusters are not opening as much as they should be.

My question is, do you think this is sometype of fish disease that killed all the fish or something wrong with the tank. The water is clear and clean however, the LR is very "dusty". I noticed when I took it out to catch the damsel, brown dust filled the water...

Any suggestions, ideas or advice would be greatly appreciated!!

 

[bertoni]

Do you have an O2 test kit, by any chance? I wouldn't think that's the problem, with a protein skimmer going, but it might be worth a shot. How about other parameters, like SG?

 

[MrChico]

I just went through something very similar I lost 5 of 9 fish and it started with my percs also I have decided that I had either velvet or brook, it is very frustrating and I empathize with you. I feel the disease started because I did not keep the salinity stable and the tank is still too new (2 months +)

 

[TinaM]

My SG is 1.025. I don't have an O2 test kit I am thinking I better get one. I did notice my blenny was hanging out in the skimmers return water flow. Lack of oxygen maybe???

I am also thinking it may be something like velvet as MrChico stated.

I think I am going to wait a while before trying to add anymore fish. If it was ich, which I am pretty sure it wasn't I will have to wait a couple of months for the tank to be safe again.

Thanks for your replies!!

 

[bertoni]

It's very hard to say. I think waiting a couple of months is a great idea. A quarantine tank might help, as well.

 

[dchao]

TinaM:

Like MrChico said, keep everything stable. Your fish might be sick now, but it could be coming from the negligence in some part of the husbandry procedures which in turn trigger the outbreak of disease. If not corrected, adding more new fish only leads to more fish loss.

For example: How do you your water change? How often and how much? Do you bring the temperature up before you do WC? How often do you top off? How do you measure salinity, swing-arm type is prone to error, get a refractometer. Do you have a digital thermometer? Limit your temp swing to less than 2 degree per day.

You could also get a alkalinity test kit, alkalinity is a measure of the pH buffer in the water. Higher alk level will help stablize pH.
I keep my alk at the high end of the recommended range (11 dKH) to keep my pH stable and it can also reduce unwanted algae growth.

To remember: Fish has wide tolerance of different water parameters, but fish do not tolerate quick change in these parameters.

 

[TinaM]

Thanks for the reply dchao. I do a 10% water change about every week to every week and a half. I use catalina saltwater, I do bring the teperature close to what the tank is. I top off with distilled water about once in between changes. I measure salinity using the swing arm type. My thermometer is digital. I do not have an alkalinity test kit. I only have the kit that tests nitrate, nitrite, amonia, and PH.

 

[bertoni]

http://www.reefkeeping.com/issues/2004-06/rhf/index.php

That article might be useful in verifying the accuracy of your swing-arm.