<a href=showthread.php?s=&postid=7251962#post7251962 target=_blank>Originally posted</a> by Jocko
I doubt you would detect a cycle on a 2 year old tank. The biggest problem you will have is the new layer of sand trapping detrius and things. This could lead to increased nitrates for quite some time. But that would not be due to anything specific about the TBS sand. A bag of dry sand from the store would have the same issue. In general I wouldn't do this unless there was a really good reason.