Replaceing your "live sand" with "dead sand" will throw of the balance of denitrifying bacteria. It will eventually colonize the new sand. If you have no fish I'd say your fine putting the corals back in. But watch your params closely and have a batch of ASW ready to go if things begin to spike.

 

Yeah, but like I said, most of the sand has been siphoned out already. I can see the bottom glass on about %50 of the tank, so it would seem that adding sand to a tank with no sand would be ok, right. BTW I do have two clowns.

 

well if the tank has no sand and everything is fine, then adding new non live sand shouldnt be a problem. The sand wont cycle since there is no life to die off within it. Eventually it will be seeded with life, but that takes time. How come u removed the old sand?

 

because, I bought uncured rock and never cleaned it. when I removed the rock to cook it because of the severe algae, the sand was disgustingly filthy. My tank turned brown. I figured that if I'm cookin my rock to keep the tank clean, then I might has well change the grungy sand too. Start anew! Now, I will have the rocks lifted off the sand, so that it doesn't occur again. I'm also planning to upgrade my return pump leading to a spray bar to blow under the rocks.

 

get a rubbermade, a small pump, and a heater... put the new sand in the rubbermade, fill with saltwater, circulate, and maintain temp.

2-3x a week... put a little flake food in there and stir the sand...... at the end of a month.. you will have sand with beneficial bacteria populations and it wont "milky-up" your water as bad when you add it to the display.

 

It may be better to replace, say, half now and the other half in a couple of weeks. What you are trying to do is much like taking all the bioballs out of the W&D filter. You only take out a few at the time while the bacterial colonises the new sand, onc this is done you take the other half out. this way you can also save some of the critters living in it.

 

If it's inert sand and you have removed most of what you have then might I suggest this. Reomve what you have left, add the new and put a layer of you old sand on top of the new. This will jump start the colonization of your sand bed.