Substrate mix

[In.a.Box]

Did a mix of MTS with STS at 70% MTS - 30% STS.
Going to Cap it with SAND.

http://sphotos-a.xx.fbcdn.net/hphoto...00448522_n.jpg

http://sphotos-b.xx.fbcdn.net/hphoto...45249070_n.jpg

http://sphotos-a.xx.fbcdn.net/hphoto...15399949_n.jpg

I made 15G of MTS

After making the mix I though I have enough for a 75g but sadly I only have enought to cover one side of the 75g. I made 15Gallon worth of MTS and still not enought. I'm aiming for 2inch of MTS + couple inch more for making hills.

I'm thinking of adding 25lb of pool filter sand to the mix to break down the MTS more, When wet the MTS stick together more ... I like the feel look of lose soil that doesn't bond together.

Or Maybe a BAG of Miracle Gro Potting mix.
Maybe a bag of Peat moss? If so which kind ?