HELP!! Zoanthids "dying" or being eaten??

[miyzfrider]

I'm a newbie and we put two zoanthid fragments into our 90 gallon tank, which is about 5 weeks old. I have a total of 5 corals in the tank, including the two zoas, one trumpet coral, two mushrooms and some green star polyps.

The issue is that our zoas appear to be either dying, or getting attacked by something. We have three emerald crabs in the tank, and I'm very suspicious they may be the culprits. All of the other corals look to be doing just fine, as do the fish and snails.

Can anyone help me understand what might be happening by the photo? Does that look like they are dying, or does it look like I may have a tank mate finding them tasty?

Only other things in the tank is a royal gramma, and about 30 snails of different types. I love zoas and really want to have lots in our tank, so I need to figure this out before I add any additional corals or fish for sure.

Water params -
Temp - 78
SG - 1.025
KH - 9
Ammonia, Nitrite, Nitrate = 0
pH - 8.4

Help!! :sad2:

 

[A. Grandis]

It could be lots of things. Hard to say by the picture.
The picture is not that close too, so...
Look like the one on the bottom has a bacteria problem, but it just look like, I can't tell you for sure. It could be internally damaged and bacteria took over it.
The one on the top looks fine to me. Give it some more time...
Again, it's just impossible to give you a 100% diagnostic over the computer.

Do you dip them before add them to your aquarium?
There are many products available today to dip corals and you could dip your zoas as well.
Many times they are just stressed for a while and will reopen after days in the system.
You can use Lugol solution to dip (8 to 10 oz of fresh water with 3 to 5 drops of solution for a minute).

Hope others will try to help more with dipping tips using other products...

Grandis.

 

[miyzfrider]

They were both fully open for about two weeks when added, which is when I added the other corals as well. It is just within the past 4-5 days that they started to look like this. I had a single polyp even come off and was held on by a small "string". I think the crabs might be chewing on them, but I don't know if zoas look like that when they die from other causes.

One other note, you can see the plug on the bottom is tipped over. that wasn't the position I placed it in. The top one is glued in place, but not the bottom one. So seeing it tipped over like that all of the sudden again points to something maybe going after them.

Snails won't bother them like that would they?

 

[A. Grandis]

Snails can do that to the plug, yes, but normally herbivore snails, like Turbos.
The zoa eating snails shouldn't be able to, nor would behave like that.
The action of eating the algae from the rock does that to the plug, if snails.
Unless it's really loose and the water motion did that.

Take a look at night and you'll probably find out if your crabs are eating/hurting the zoas.

Crabs are not aways a good thing to keep in our tanks.

When they hurt the zoas bacterial infection could take place.

Grandis.

 

[miyzfrider]

Yeah, I think to be safe I'm going to pull them from the tank. I have two in the sump now, awaiting the third to appear so I can get him out too. I'll take them back to the LFS and see if they will give me credit or something toward a new zoa frag. Catching the two wasn't as bad as I expected. They sure grab the rocks firmly, but they weren't fast enough to get away from me.

Where in Hawaii are you? My wife and I visited Maui last month and that's why we're doing a tank...decided we wanted to put a little Hawaiian reef in our living room. Kole Tang and Yellow Tang are two for sure fish we plan to keep!

 

[A. Grandis]

:thumbsup:

I'm in Oahu.

Grandis.

 

[miyzfrider]

Visited there first on the trip to go see Pearl Harbor, the Dole Plantation and the North Shore. You sure live in a beautiful state!! Thanks for the advice.

 

[A. Grandis]

Visited there first on the trip to go see Pearl Harbor, the Dole Plantation and the North Shore. You sure live in a beautiful state!! Thanks for the advice.

You're welcome! Good luck to you and your zoas!!

The only bad thing about living here is that we can't have the beautiful corals you are able to keep on the mainland. You guys have wonderful zoas available there!!
But we still can do some snorkeling and enjoy some of them in the ocean.

Aloha,
Grandis.

 

[kalgra]

Funny i should come across this. A friend of mine just found his large emerald munching down on his. I personally have never had issues with my crabs other than the occasional trampling. Have you check for pests (nudis) or other irritants such as asterinas?

 

[miyzfrider]

I have looked closely for other pests and don't see any, at least to my untrained eye. I did purchase some Seachem Reef Dip and dipped the one zoa frag I had that seemed to be doing ok. Then when I took the two crabs back, I got another zoa frag and dipped that before putting it in the tank. This AM all looked good. The other ones had definitely died though, so I pulled those out (cue taps in the background) .

So now I have two zoa frags that appear healthy and one remaining emerald in the tank. I think the crabs were the culprits, and just not enough food for three to be sustained. Hopefully now that I only have one crab, things will balance out. We'll see and I'll definitely be keeping an eye on things very closely! I also noticed my trochus snails up on the frags. I doubt they'd do more than annoy them though from what I've read, but maybe they can damage the zoas too.

 

[kalgra]

Personally I love the trochus snails. I have lots of them. If there are up on the zoas they will definitely irritate them causing them to close up but I cant really see any reason why they would cause damage unless you just had one or two that were constantly camped out on top of them.

Forgive me if I am mistaken it sounds like you are fairly new to the hobby? I'm no expert either but it took me about 6 months and allot of learning tiral and error before I was able to keep and grow nice zoas and palys. Sometimes they just die and we dont know why. Zoas and Palys are not always as easy as some make them out to be especially the cool ones.

If you are new to the hobby just be patient research as much as you can and expect to lose some things along the way. Once the tank is established an your system is stable things will really start to take off for you.

 

[miyzfrider]

Yup, I'm new. The 90gallon we have is only about 5 weeks old and these two zoas are our first. So yes, we're learning as we go! Thanks for the help and encouragement!!