My 120 is 7 months old and I have an area where I want add more sand. Is there any danger to adding live sand to a tank that has already cycled and currently has fish?
I think it depends on how much sand you plan to add and how big an area you want to add to. If you put the sand on heavy it is going to smother the fauna underneath it which will cause some die off. If it is only a small area that is not a problem but if its a bigger area then I believe I would put it in a small area at a time.