Homemade Substrate

[B-2]

I have a 50 gallon community aquarium that has been running for two years. Most of my plants are doing fine, but I heard they grow better with a clay substrate. I have mostly sand as a substrate with some rocks and gravel mixed in. The sand is the kind you buy in bulk for various purpouses (filling in holes, adding to cement, putting under above ground pools). My dad bought a dump truck load of it for our huge sand box. The gravel is normal gravel I collected from a stream in my woods. If I dig deep enough (more than 8 inches) in the stream, I will reach clay. The clay is dark gray and it is sticky, smooth, and can be molded easily, exactly like the clay you can buy at an art store. It is very pure and there is no dirt in it (I can tell by the way it sticks together). I was wondering if I could mold it into little pebbles, fire it in our wood burning stove for a few hours, and add it to my aquarium. Would it help my plants grow at all? Also, should I boil it before or after firing it to sterilize it more? I don't want to buy clay substrate at the pet store when I can make my own.

[rahendricks]

I use topsoil as a substrate. About an inch covered by about an inch and a half of fine gravel. I didn't do any sterilization to the soil, but that was on a new tank that was planted and allowed to cycle for a month. You wouldn't want to try this on a tank that was already set up; it would be a mess. I have seen comments on the net from people who have made their own clay balls that they pushed into the substrate near their plant's roots. You might want to do a search on clay substrates to see if you come across them. I have no experience with trying this. It seems to me I read a warning about using submerged soils from stream/lake beds in an aquarium. I'll see if I can find the warning. When I was researching soil substrates it seemed that most people were using what they dug up out of their own yards.