Originally posted by agarr
you can put live sand on top of the coral,it is your better choice...It does work fine; I have done this,its in my tank right now. All fish are happy,parameters perfect,my tank is great. Its so stable;i just bought new lights for which to grow coral.:joy:
It is NOT your better choice. Just because you have done it does not mean it is your better choice. The problem with the crushed coral is the long term effect, not the immediate effect. Before you state such a "fact" like you did, know why crushed coral causes problems. It traps detritus and dirt under it (which break down into nitrates). Crushed coral is hard to clean.
If you put live sand on top of your crushed coral, you are definitely asking for problems. Let's just use this scenario. He has a 2" thick substrate of crushed coral right now. If he were to put live sand on top of it, he will be trapping all that dirt that is in the crused coral underneath the live sand. You may test for 0 nitrates, but that does not mean they are 0. They are all being trapped in the substrate. How are you supposed to get them out when you have it like you described? You cannot siphon your crushed coral anymore because you have LIVE sand on top of it. You are not supposed to siphon live sand. You should only be agitating the top of the sand. Everything else should not be disturbed by you because that is where denitrification occurs.
And just as a clarification, taking out the substrate will put nitrates into the water column, because the coral traps nitrates under it. If you are removing it, you are disturbing it and causes its components to go into the water column. However, a water change and the use of Cycle will help remove it.
