dying fish

[fishfan12]

the tank has a medium filter and the heater works fine and keeps the tank at 73 degrees.

 

[fort384]

did i mention: only my weaker fish have died. i keep my fish in pairs and only the smaller of each pair has died. could that be signifcant?

I would expect this if there is a disease present. It is going to affect the weaker fish before the stronger ones. I think all it is saying is there is something in your tank causing disease, and the fish with weaker immune systems have succumbed to it first.

When you say medium filter, what kind of filter is it? Hang on back (HOB) or canister? Also, how many GPH does it pump, and what kind of media are you using? Are you running anything in it like activated charcoal?

The temp seems on the low side, but not enough to cause a lot of stress that would lead to disease I wouldn't think. I would expect more bacterial/fungal disease outbreak at a higher temp as opposed to a lower one.

 

[fishfan12]

my filter is a HOB and it uses activated carbon. i don't know how many gph it does, it is an aqueon medium filter that came in starter kit 14.

 

[fort384]

ok if it came with the kit, it should be at least able to keep up. I am stumped as to any other causes / sources, especially since we are talking about 2 separate diseases that have infected your fish. There are antiobiotic treatments that can eliminate infections in the tank if it is residual. It is something to consider using. Be prepared for a mini cycle if you go with an antibiotic treatment, as the antibiotics can also kill your good bacteria.

The antibiotics should be a last resort though. It is better to identify and treat causes for infection than to jump straight to the antibiotics.

Have you added anything at all to the tank in the past couple of weeks or so, like a piece of driftwood, etc?

 

[fishfan12]

i actually haven't. everything in my tank has been there from the start.

 

[fort384]

Boy I am stumped fishfan. I am sure some other folks will see this and have some further ideas. I would hold off on any antibiotic treatment, and get a few opinions before proceeding.

Jim had a good idea, you could actually turn the heat up a bit, which would cause a bacterial infection to present itself quicker, and may help get a better diagnosis. Beyond that I really don't know.

 

[fishfan12]

ok, thanks for your help. ill turn it up to 75

 

[missileman]

One other thing to try, not knowing what the actual cause is.
Melafix is an organic treatment for bacterial infections that will not harm your biofilter and is easy on the fish.
May be worth trying. I would rather treat with something like this than to wait until more fish get sick.