Would appreciate some advice on a new planted 75 gallon tank I'm establishing. The substrate is about 1 1/2 " organic soil capped with fine gravel (#3 grade) ranging in depth from 2 to 3 1/2 ". Based on some recent reading, I'm concerned about potential anaerobic conditions setting up and killing future inhabitants. Are my concerns overblown? Are MTS snails a good option to promote substrate aeration or would I be introducing a future nightmare? BTW, there are no fish in the tank yet since the formal cycling process will begin next week.