What type of algae?

[Myka]

Originally Posted by chromakey

I did reuse the sand when I moved the tank last year. There was a lot of debris in it. This is my first saltwater tank. Do you think it is worth changing out the live sand? I was thinking going a bit shallower.

That's a reasonable idea. It doesn't look dirty in the picture you posted, but changing the sand could do no harm provided you do it right.

Use a 1/2" or 3/8" hose to siphon out 1/4 of the sand bed in a straight line down to the glass. If you expose any black/grey areas cover them up with sand. In a week do the next 1/4. Repeat until it is all done.

When you add new sand, "live sand in a bag" is a good marketing scheme, but that is all. However, the sand is pre-rinsed and not as dusty as dry sand even if you wash the heck out of the dry stuff. So the so-called "live" sand is a good choice.

If you go with a 1/2-3/4" sandbed you can vacuum it regularly to keep it clean.

The livestock: 2 clowns, 1 flame angel, 1 sixline wrasse, 1 tailspot blenny, 1 tuxedo urchin and 2 cleaner shrimps.

That's a fair amount considering the size of the tank and the setup. Be sure you aren't overfeeding them.

Have you had issues chemical warfare with various corals?

Oh yes. Carbon usually settles the problem. I wrote about allelopathy a bit in