what does aragonite do for a tank?

what values does aragonite have as a substrate for marines? i have a substrate 4 inches thick.

 

Aragonite buffers your tank to help maintain a PH of 8.0-8.4. Also contains other trace elements beneficial to your tank.

 

Also, if your substrate is 4 inches deep, it begins to qualify as a deep sand bed (DSB) - which ranges 4-6 inches. This can help provide anaerobic zones for nitrates to be converted into free nitrogen by anaerobic bacteria. This is a good thing for you. But be careful not to stir up the deeper levels of the sand too much after a few months, as it will liberate chemicals into your tank that are toxic to your livestock.

 

ok cheers