Mystery Problem

[RoseFishWatcher]

Not much experience with this type of problem, but here are some random thoughts that may help:

Maybe it's worth trying a drip acclimation? If your water is significantly different from the place you buy them, this could help.

Since plecs and corys are catfish, they're scaleless, so may be more sensitive to some things. Normally it's just a problem with copper meds, but unless you dose copper into your tank all the time (I guess an algae destroying product maybe) that seems unlikely.

Only other thought I had was oxygen. Sounds like it should be ok in your tank, but with insufficient flow there will be less O2 at the bottom of the tank.

 

[SumpNFishy]

I'll give this a try

After searching around on this and other forums I've decided that my under gravel filtration might be the problem. It seems to cause high nitrate levels according to what I've read and that is a problem I've been dealing with.

Another observation was that in my 29 gal tank, the plecos seemed to be fine when I saw them on the sides eating alge. The next day they were on the bottom dead or dying. I think they swam to the bottom to nibble on something and became sick quickly enough that they couldn't swim back up to the sides.

This weekend I'm going to tear down the 29 gal and remove the UG trays and then do a complete cycle before adding any plecos or catfish.

On the 95 gal I think I might be dealing with an aggressive fish who killed the pleco and cory I added a week ago. Not sure how I'll figure that one out....

Thanks for all the informative replys. Hopefully I'll get to where I can have scavengers as part of my "Happy" community tanks.