Leather corals withdraw too frequently

[JKurtz]

Hello everyone! I've got a 75-gallon reef with 90 pounds of Fiji live rock, 1 bubble coral, 2 colonies of zoanthids/palythoa, 1 sea rod, three small leather corals, 1 mature leather, 1 Kenya tree coral, 1 briarium and a star polyp colony. The only fish in the system are a Kole tang and a mandarin dragonet.
My problem is, the leather corals, with the exception of one small toadstool, shut down and shed too frequently--often after only a day or so of being opened.
The rest of the corals are beautiful and growing. When open, the leathers are healthy looking and seem to be gaining size.
Currently, I'm adding 2 teaspoons of Liquid Gold every other day, 3 drops of Lugol's once every week, 11/2 teaspoons of Kent Marine's strontium and molybdenum every 4 days, and I top off with kalkwasser every other day.
PH is 8.4, SG is 1.04, temp is 78 to 79 degrees Fahrenheit.
Lighting consists of 4 55-watt PC's (2 actinic and 2 daylight). Filtration includes a venturi protein skimmer and a wet/dry biofilter. Water movement is provided by one power head and the return flow of the wet/dry, which are located at opposite ends of the tank.
I perform a 10-percent water change once a week and treat the tap water with AMQUEL. However, I do not use RO or deionization because my dealer said it wasn't necessary with our local water. Big mistake?
Anybody have any suggestions?

 

[davelin315]

If your salinity is at 1.04, your corals should be dead. That's like floating in the Dead Sea, that water is very very dense and probably cannot hold any oxygen level suitable for anything besides brine shrimp to survive. You've got to get it down to between 1.025 and 1.027, otherwise say bye to all of your living stuff.

And don't use the amquel, if you use tap water, just use a dechlorinator that doesn't add anything to your water.

[ September 24, 2001: Message edited by: davelin315 ]

 

[JKurtz]

Oops! Make that specific gravity 1.024!

 

[davelin315]

With the typo, the only thing I can think of is something is in your water that is irritating them. My guess is the amquel has something to do with it, or maybe one of the things you are dosing is being overdosed.

 

[JKurtz]

Maybe I'll try cutting back on the additives and eliminating the amquel as a first plan of attack. It certainly can't cause any harm. Any possibility that the "mature" leather is somehow inhibiting the smaller specimens? I can't say for certain, but it seems like the problem became more acute after adding the large leather--although it, too, shuts down rather frequently. The thing that really baffles me is why that one toadstool remains open almost constantly while the others can't seem to "make up their minds."

 

[davelin315]

Sarcophyton and Lobophytum species have been known (I think it's both of them), as well as other soft corals, to release chemicals into the water that will inhibit the growth of other corals, so that very well may be the cause of your problems. Try running some carbon on your tank on a constant basis, and see what happens. Good Luck!