Corydora substrate

ninja · Post by **ninja** » 27 Oct 2007, 09:39

Hi all,

I'm planning a 10 gallon tank stocked mainly with various species of corydoras and perhaps a school of smaller fish.

I plan to use fine sand as a substrate as I have heard this is what corys thrive on best. However, I have been told that all tanks need a substrate of two layers, and that sand should never be the top layer as it caps off the bottom layer from air/water exchange. Instead, I have been instructed to create "islands" of sand substrate around the tank.

I would really like the entire base of my tank to have at least a top layer of sand, not just for aesthetic purposes but also the health of my catfish. Is it possible to use only one substrate (fine sand) in the tank, or am I required to use two layers of substrate? What are the two layers for?

snowball · Post by **snowball** » 27 Oct 2007, 14:09

Sand alone is fine, just don't make it too deep - 2cm / 1 inch max is best, else it can get anaerobic pockets.

Two layers is really only useful for heavily planted tanks in which the bottom layer can contain a mix of soil or commercially available substrate mix.

If mixing substrates remember that the finest grains will eventually work their way to the bottom, so sand over gravel wont work (at least not for long).

fwiw, I have used the 'island' technique in larger tanks, putting sand in one corner and the rest of the tank being gravel. however it does require regular maintenance or it will eventually mix.

apistomaster · Post by **apistomaster** » 27 Oct 2007, 14:34

One 12 lb bag of Flora Base is just right for a ten gallon tank. The plants will grow extremely well and it is easy on Corydoras barbels.

ninja · Post by **ninja** » 27 Oct 2007, 17:01

I don't plan on heavily planting my tank so I will probably use pure sand. I'm not sure they sell Flora Base here. How well do plants grow in sand? Is it advisable to pot them first?