I need help with my Zoanthids/Palys fast..

[LexSkizzle]

So over the past several months (6 months or so) I noticed that a couple of my zoa/paly colonies are starting to melt away/die off. Not sure what the problem is. All my parameters seem to be stable and fine.
Nitrate: 0
Nitrite: 0
Ammonia: 0
Calciium: 460
Phosphate: 0
pH:7.9
Temp:79-81
Alk: 10

I tried the VC dosing and it didn't do anything but cause my Alk, pH & calcium to slighly drop(ALK:7/pH:7.8/Ca:400) and also seems like some of the rock was losing its purple color when I started dosing. My parameters have always been stable and do not ever change with my current regimen which is why I'am linking the change in alk, pH and CA to the VC dosing since its the only thing I did different.

Well, I have stopped dosing VC after two months b/c I didn't see any positive affect but my zoas are still slowly melting away. Alk, pH, and CA are back to normal once I stopped dosing. It's wierd b/c some zoa/paly colonies are doing great yet some are just melting away. All my other corals are doing great.

Any help, tips, advice? What should I do? I love my zoas and can't stand to see so much of my favorite ones die off anymore..

[Pufferpunk]

There is absolutely no way VC will affect your Ca. What dosage were you up to? High doses as high as 50-100ppm may be necessary for extreme cases. It is mentioned over & over to test often & adjust your alk/pH as you are dosing.

Your pH should be around 8.3.

[mscarpena]

SOmething similar happened to me and a fish I had was nipping at them. Just nipping, but not eating. He did not bother all of them at one time, but seemed to pick on a few colonies then move to a few more after those had died off. Just watch your tank for some time and see if anybody's picking.

[LexSkizzle]

Pufferpunk-
I dosed as follows:
1/8 tsp 2x day for 1 week
1/4 tsp 2x day for 1 week
1/2 tsp 2x day for 1 week
1 tsp 2x day for 1 week
1 1/2 2x day for 3 weeks

pH is a bit lower than I would like it but its always been between 7.9 and 8.1 and I have never had any problems which I have noticed for the past 3 years b/c of it. Have you ever dosed 50-100ppm without any adverse affects? If so, I may try that

As far as a fish picking, I haven't seen any of my fish do so, but I will keep a closer look to our rule that.

Any other ideas?

[stoneroller]

Check for pests at night.

[mikedelgado]

and look really close for tiny nudis