I have a 135G tank that I'm in the process of setting up and I need some help on a substrate. I was thinking about going with silica sand because it's inexpensive to buy in bulk (I estimate I need close to 400lbs), but I'm concerned with compaction and maintenance issues due to the small grain size.
My only real requirements are that the substrate be black (or at least primarily black/dark in color) and that I can get the substrate for fairly cheap.
I tried to do a soil based substate once before but was unsuccessful. I had horrible algae blooms (I'm guessing that it was because of too much organic matter in the topsoil).

Can anyone help me with ideas for how to achieve my goals for a substrate?

Thank you,
Kevin

3M Colorquartz comes in black, and is a silica sand. You can possibly get it at a business near you that finishes swimming pools, floors, or possibly roofs. Just phone around. This stuff comes in more than one particle size, so you need to get one that has 2-3 mm grains, and I don't recall what they call it.

There's no compaction, it's more an issue of the build up of organic matter(dead roots, fish waste etc). so a deep vacuuming every 12 months of a good hand turning after uprooting a certain section is wise.

I think the Black Flourite sand meets some of the considerations you are concerned about, 300 lbs ought to do well.

If you add rock, Wood, consider that as filler also
So you might call around and see if you can get the flourite first, as well as search for the Black silica sand.

The black flourite sand from Seachem looks good.

Regards,
Tom Barr

Thanks guys for the knowledge and suggestions.

I found a dealer that will sell me 400lbs of black silica sand 1/20" (which I think converts to 1.25 mm) for just under $200. Compared to the retail stuff like flourite and eco-complete, that's a huge bargain to me. Since it sounds like I don't need to worry so much about compaction and getting aneroebic conditions, I think that's the route I'll go.

Again, thank you!

Cheers,
Kevin

Kevin, add some peat and some fresh mulm from a filter etc to the bottom, a light dusting etc. You might even consider some osmocoat, say 10 grams or so(about 2 teaspoons or so).

At least do the Peat and mulm.

Regards,
Tom Barr