Flatworm Problem

[fishycouple]

I originally posted this in the Reef section and no-one even commented. Maybe I'll have better luck in this category.
Hi all:
I have an infestation of flatworms. They are all over the glass and the few corals I have. I have a leather, frogspawn, bubble, giant mushroom cup coral and a florishing crop of yellow polyps.
My fish are yellow tang, flame angel, small huma huma, and a equally small clown trigger.
All of the fish get along and leave the corals alone. Of course the hermits and the snails are long gone.
My tank is 55 gallon, has about 40 lbs of live sand and about 55 lbs of live rock. The rock and the back of the tank are covered with purple coralline algae. I am running a sump with bio-balls and a CPR back-pac skimmer in the sump. All of the water parameters are perfect and there are no problems there. Even the flatworms are happy.
I know I need to freshwater dip the rocks and the tank to eliminate the worms, but I don't know how to go about this without harming the fish.
I am considering replacing the 55 gallon with a 75 gallon tank as it will fit the same stand and the Power compact lights will still fit.
Now the big question...if I replace the tank and replace the sand with new (to eliminate any flatworms there), and I freshwater dip the rocks, clean the sump (without cleaning the bio balls), and re-fill the tank with fresh salt-water, where do you recommend I keep my fish? I have already located a new home for the corals, and the new owner (a lfs) is probably capable of eliminating the worms on the corals. How long will I need to wait to re-introduce my fish? I am going to only have fish with the live rocks and no corals, well maybe some polyps or other easy to keep corals.
Could I safely re-use some of the water from the 55 without re-introducing the dreaded worms?
As near as I can tell the worms hitch hiked on a coral to my tank, and I have tried sucking them out with a syphon when changing water, but I cannot get them all and they come right back.
Any help would be appreciated.

 

[beth]

So what's the problem with the "flatworms"? How do you know they're flatworms? Have you IDed them?
Flatworms, and worms in general are natural components of tank fauna. Yes, some are detrimentally parasitic, but unless you are having problems with parasites attacking a coral or clam, etc., then I don't see that this is something that you should worry about.
If you want to dip rocks, then you basically use distilled or RO water, same temp and pH as your salt water. But I see no reason to do this. You will never "eliminate" parasites from a reef tank, no matter how many dips you do.

 

[fishycouple]

Thanks for the reply Beth.
Yes they are flatworms, and they are attacking the leather (which is fairly easy to vacuum). They are also attacking the scarinina and the cup coral, both of which have skin so thin it is impossible to vacuum without harming the animal. They are covering the corals and blocking the light to them.
I know they do no physical harm, but they are terribly ugly! It is an embarrassment to have them on the glass and the corals. They are hard to see in the sand or on the rocks, but that is where they wiggle to when knocked off of the glass, so I'm sure there are some in the sand and the rocks too.
I have tried the 6 line wrasse thingy, and it ignored them, so I returned him before the triggers decided he was food.
Before I had the triggers, I tried a mandarin, but he didn't like them any better than I do. Unfortunately he died. I guess he didnt like the Tang or the flame angel, which were the inhabitants at that time.
When they are wiggling in the water, none of the fish will even nip at them.
My plan is to switch the tank soon anyway, so the dip won't be too much of a hassle. What concerns me is how to keep the fish alive during the switch of the tanks, while I clean the worms out.
Thanks for your interest in helping me with this switch, which is almost like moving to a new place.
Rick

 

[thomas712]

I once read a posting on some other site where the guy accidently did a water change with just R/o water. The resulting drop in salinity resulted in a major reduction in his flatworm problem, his corals didn't like it either and it took several weeks for them to recoup. I have also read a posting where a guy found a shrimp that is the natural preditor of these flatworms but for now he is not telling anyone which shrimp it is.
Thomas