Cories with Riccia Fluitans (Crystalwort) Carpet

[Merlin]

Hey Guys,

I've never had cories before, but I'm in love with the pygmy and albino ones at the LFS. I just set up a new 20 gallon tank and was wondering if anyone has had experience with cories in an environment where the substrate is (or will soon be) almost entirely covered in riccia fluitans (crystalwort) and dwarf hairgrass. The substrate itself is fine black gravel, which I understand is not good for their barbs, but if I grow the tank the way I envision it, the gravel will be pretty densely carpeted in plants.

Should I scrap – or at least cut back – on the crystalwort and add a layer of fine sand for the cories – or will they be ok with a plant covered substrate? I have noticed that they seem to swim mid-level in the aquarium most of the time, however I know they are bottom-feeders and I'd like them to behave naturally, not just sit around and survive.

Any advice? Or should I just stock the tank with tetras and save the cories for another day?

[Dave66]

The pygmy corys spend a lot of time in a school hovering above the substrate, and only come down like regular cory cats to feed. Pygmy corys were called tetra corys in the old days because of their schooling nature. You could easily house a dozen of the pygmy corys.
As far as the albino, it depends on which of the two species that are sold in albino form how large they'll be. If it's C. aeneus, the albino corys will grow to 3 inches. If it's C. palateus in albino form, they'll top out close to four inches.
And since they should be kept in a school of at least six, that's a lot of albino catfish for a 20.
Only problem with the riccia is the corys' natural foraging will break off pieces, and those pieces will grow into Ricci's natural floating form. You can avoid a lot of that with pygmy corys, which are so small at an inch long, they make very little disturbance with their foraging.
You could leave a dark sandy area in the main swimming area, since it'd make it a lot easier to feed the corys correctly.

Dave

[Merlin]

Thanks Dave, I think I'll pick up a dozen pygmy's then, and leave some sandy area to feed them. I was under the impression that the C. Aeneus variety of albino cory was somewhere around the pygmies in size for some reason. At three inches they're way too big for this tank.

I appreciate the info.

Mike