Bad hitchhikers...how to rid without nuking rocks?

[vertwake]

My tank has been up for about a year and a half. During that time I have removed 43 crabs from my tank. I can still count 5-7 at any given time. I'm frustrated as I can't let zoa colonies grow on my rocks. Something eats them all. (not fish). Happens overnight. I've lost an entire 17 polyp colony overnight to a crab. I know this because I noticed a couple of polyps gone so moved entire rock to QT tank. Next morning all were gone.

I can't seem to get them all extracted. I'd like to flush them out without nuking all of the rock. What is the safest way? Dip in RO water? Peroxide?

Catching each crab individually with traps or by extraction simply isn't working effectively.

Any suggestions, ideas?

 

[secretreefer]

Well.....i fill up 2 large tubs. one with tap water and one with tank (matching params) water and a large airstone bubbler going. get garden hose. shoot the rock and all it's crevices good with the garden hose (even under the water in the tub if you want to reduce splashing) and then let it sit in the freshwater filled tub for maybe an hour. then check out the rock to make sure everything is out and put it in the tub with tank water. i've used this technique alot and havent' had any problems. Now if you have aptasia on the rock it's a different story..... Great thing about having a tub with tank water near is if you find any hermits, etc..etc..beneficial reef critters that get removed, you can just drop it in there.

 

[vertwake]

Thanks for the suggestion. If I do this for all 100+ lbs it won't make them start a new cycle will it? And is it safe to put it straight back into the DT after blasting it in the tub? Figure I have to do it all at once or the crabs will just spread to the different rock formations...

Well.....i fill up 2 large tubs. one with tap water and one with tank (matching params) water and a large airstone bubbler going. get garden hose. shoot the rock and all it's crevices good with the garden hose (even under the water in the tub if you want to reduce splashing) and then let it sit in the freshwater filled tub for maybe an hour. then check out the rock to make sure everything is out and put it in the tub with tank water. i've used this technique alot and havent' had any problems. Now if you have aptasia on the rock it's a different story..... Great thing about having a tub with tank water near is if you find any hermits, etc..etc..beneficial reef critters that get removed, you can just drop it in there.