Tank Cycle


New member
I am in the process of setting up a 10 gal refugium (I am limited on space) for my 90 gal reef. The 90 gal has been up for about 10 months. If I add about a 3"- 4" base of OOLITE live sand to the refug will that start a cycle.

I am new to this so I hope this is not a dumb question.


Premium Member
I did the same thing at one point a few years back and did start a short cycle that really didnt do damage to the tank. If I may offer a suggestion, why not add 6-7" of live sand and get the benefits of a dsb? Also, when I did it I added a few lbs. of live rock that was fully cured. That, I believe, kept the cycle down to a few days. I did a couple 20% water changes and didnt loose anything.


New member
I see no reason adding a bag of unused sand would start a cycle. You should seed it with sand from another tank.


New member


Why would adding a few pounds of sand and a bit of water volume to an established 90g start a small cycle? I've added new sand to my tank all the time and never experience that.

I'll be adding a 6g refugium onto my 15g grow out. My plan is to add some dry sand to the fuge, add saltwater, throw in a couple cups of live sand and put it online and it should be good to go!