Catfish and/or Pleco's in AP systems

[Linda Logan]

I'd like to add some fish to help clean by tank and sumps.  Is anyone using catfish or pleco's.  What other fish are helpful.  Any downsides?  I've read that large pleco's can kill other fish.  Any experience with this?

Thanks

[Linda Logan]

I have the white liner on my fish tank.  What I see is a brown coating on the bottom and sides.  I don't know if this is algae as I think of algae as green.  I can clean it off easily.  From suspension it mostly flows into my sump which is where I pump from into the beds.  Once a month or so I clean this out with a vacuum pump.  It is this brown stuff that I wanted the pleco's to clean.

I have a DO meter and checked my DO,it is running around 8+ in water about 75 degrees.  I think of myself as such a novice that I'll have someone else check this to verify my results.

I also don't know how clean the FT should be.  I've seen some with water you can't see into and then heard other say there's is totally clean on the sides and bottom.  Any guidelines here other than fish seem well and plants are growing.

As always, thanks for your help

Linda

TCLynx said:

If you are having green water issues, I don't think the Plecos will help.

If you are having green surface algae in the tank, the plecos will eat that but I don't really think surface algae is generally much of a problem in aquaponics and tilapia will eat it some too.

[TCLynx]

I wouldn't worry about cleaning out the brown slime.  It is probably a combination of bio slime (the bacteria that convert the ammonia into nitrite then into nitrate) and small particles that get caught in it.

A healthy system should have a fine coating of bio-slime on every surface in the system.

Only real reason to clean things off is if you are running a display tank and need it all crystal clear so people can view your fish and the pretty display you have set up with them.

[Linda Logan]

Thanks for that feedback.  Very helpful to have an understanding of what it is and it's function.

TCLynx said:

I wouldn't worry about cleaning out the brown slime.  It is probably a combination of bio slime (the bacteria that convert the ammonia into nitrite then into nitrate) and small particles that get caught in it.

A healthy system should have a fine coating of bio-slime on every surface in the system.

Only real reason to clean things off is if you are running a display tank and need it all crystal clear so people can view your fish and the pretty display you have set up with them.

[Jon Parr]

I too have plecos in every single tropical tank to clean the walls. Like TC said, the small ones do a splendid job of eating slime and algae, and the big ones tend to play dead until feeding time and then steal food. Plecos are nocturnal, and can definitely wreak havoc to tankmates at night. I also have catfish in every single tank and raft trough, just as sweepers and to eat what they can find. If green water is the problem, then mossambicus tilapia are your friend, as are daphnia and brine shrimp.