paswed

I have a 120 gallon tank it has 90lbs of live sand and 30lbs of uncured rock in it and snails, blue and reds hermit crabs, how long will it take to cycle ,can i add more uncured rock as i buy it

also

I have a protien skimmer and a cansiter filter and an another filter

sgould

I have cycled with live rock twice...first time took 12 days, 2nd took 15-17. Yours could go faster or slower. As to adding more uncured live rock in the future, no, you shouldn't. When you buy more, cure it in a seperate container and only add it to your tank once it has finished curing. This is because you will get a large ammonia spike during the curing process, and could quite easily wipe your tank's inhabitants out.

paswed

I have uncured rock in with my crab and snails will that be ok this time or do I need to remove the rock

sgould

If you have another tank or container that you could put the crab/snails in for a couple of weeks, that would be better. That way you can leave the rock in the tank to cycle it for you.