zoa trouble

[larrynews]

so i have a batch of zoas that are weathering away so i have been looking every night to see if i have any pyramid snails or anything and tonight i found one of those broken star fish, my question is , is that eating my zoas and that is what is killing them or is it eating them because the are dying(eating the died tissue
thanks

[harleyrider]

I am new to this hobby, but from what i have read and heard from a lot of people, that star fish are bad for corals, and you shouldnt have them in a reef at all....again just what ive heard, dont know for a fact!

[Reefd Up]

I am new to this hobby, but from what i have read and heard from a lot of people, that star fish are bad for corals, and you shouldnt have them in a reef at all....again just what ive heard, dont know for a fact!

Not at all.  There are probably thousands of species of starfish...and many of them are reef-safe starfish.  It's unfair to label them all bad.  Yes, some starfish do eat corals (crown of thorns, chocolate chip, SPS-eating-starfish), but most are just detritus-eaters. 

Chances are, it's just eating the dead tissue.  But, I would still post pictures for us to identify the type.  To diagnose the problem, please post your water/tank parameters and pictures of the zoanthids/starfish.

[larrynews]

thanks its the same kind i have had in there for what seems like ever but i'll try tomorrow and get a picture

[Reefd Up]

They're probably just asterina starfish...very harmless.

[joelbegt]

What exactly do the zoas look like?  Do you know what zoa pox look like?  Zoa pox is cured using furan 2 dip.  Have looked for nudis?  The nudis alway seemed to die after a 2-3 min. freshwater dip.  I try to dip all new zoas that I recieve. 

Don't know if that helps you out any,
Joel

[joelbegt]

close up macro pictures of the polyps may help if you have them.

[Joel]

I dip all of my colonys/frags right before they go in my tank.  I just use fresh r/o matched to the tank temperature. Get the colony to close up (wont hurt if some stay open), and place it in the freshwater for about 3min. or so.  during the last min. i try to swish the colony around in the water and dip it in and out of the water to dislodge any loose material. freshwater will pretty mush take care of any pests.  A fw dip WILL NOT help with a fungus.

 

Using Ro/Di water that has only been temperature adjusted is very harmful / stressful to organisms that are being dipped, In some cased it will even kill some animals having that radical of a ph differance. Better freshwater dip methods are to adjust your ro / di water to have the same ph / alk as well as the temperature of the Saltwater tank. This will significantly decrease the shock of the process. It is also note worthy that many corals will not survive even the most brief fresh water dip so use caution.  (montipora sp. for example)

Agreed that F/W dips on Zoa typically works well to rid most nuisance parasites / pests. This method is very affective on planeria sp. (flat worms) and on Nudibranch sp.. I have even killed hydroids performing f/w dips. Another method that I am fond of extended baths in iodine / lugals solution in a container of saltwater removed from the aquarium.  Iodine is a very strong oxidizer and will kill many parasites and act as an antiseptic on damaged tissue. I will do this method for periods of minutes to an hour or more depending on the coral and the strength of the solution. I would advise aeration while performing this method as well.

The above methods don't seem to be affective on Sundial snails, they need to be physically removed from the colony.

As per the starfish, there is more than one kind of small white starfish that is found in our aquariums. Of them there are some that are a coral predator and some are not. I would remove it to be on the safe side and look up some pics on line to determine the specie that you have. Because some of them reproduce by division, it can be tough to identify the specie. I got a ton of them in one of my coral tanks that are completly harmless but I have seen similar looking starfish that would eat corals.

Your always welcome to bring the zoa colony in to the shop for inspection or to attempt a treatment if you'd like too.

See ya...Joel

[Reefd Up]

Usually when zoanthids "weathering" away, it's a water quality issue, not a pest.  If they were zoanthid-eating-nudibranchs, he would see actual damage.  Could be zoa-pox, but he hasn't mentioned any spots.  Could be zoanthid-spiders as they tend to just pester the colony.  

Before taking drastic measures like a freshwater dip...just post your tank/water parameters.  I have a feeling your problem is there.

[Joel]

Couple good links about those "little white star fish"


http://www.wetwebmedia.com/asterinafaqs.htm

http://www.wetwebmedia.com/asterinafaqs.htm

Good point about water parameters Nikki, I assumed that this had been checked but it never hurts to double check.  I also would think that if it was a water quality issue that other corals would have shown some signs of stress as well.

Joel

[larrynews]

thanks, no others are bothered so i'm wondering if it was just something that happened even ones on the the same rock are fine

[jhart]

Just out of curiosity, what parameters are you most interested in regards to water quality? I bought some rocks a couple years ago that were covered in zoa's and now maybe 25% remain while others are growing and doing pretty well. My water has usually been good, ammonia and nitrite have always been zero and nitrate rarely gets above 2.5.

[Reefd Up]

Just the fact that water parameters aren't posted through this ordeal really concerns me.  After trying to diagnose countless problems over the years...the ones that don't initially post their water parameters are usually the ones that haven't tested in a while...and that's where the problem usually lies.  If my tank starts looking bad...first thing I do is either a water change and/or test the chemicals.  Just b/c one coral is looking bad and everything else is looking fine doesn't mean it's not a water quality issue...it just means that one coral is more susceptible to that one thing (zoanthids aren't like every other type of zoanthid...they vary in many ways...especially when collected from different regions.)

It's really hard for us to help when we don't know anything about the tank...no parameters, no light details, water change regimen, dosing, skimming, blah blah blah.  All we know is that your zoanthids aren't doing well.  Most likely, it's something really easy to fix...something very obvious that would stand out to us, but might not stand out to the person that has been looking at the tank every day. 

Without knowing anything else...and assuming everything in your tank is 100% perfect (which, I'd get those nitrates down to non-detectable)...the only other thing I can suggest is vitamin C dosing.  It's been shown to help with zoanthid melting, but I wouldn't tell anyone to try it unless I knew everything about their tank and still couldn't find a reason. 

[jhart]

BTW sorry for jumping into this I've just had similar issues. My nitrate is typically somewhere between 0 and 2.5 (even with a 20% bi-weekly w/c), kinda hard to tell exactly with my Red Sea test kit. I typically test for pH, ammonia, nitrite, nitrate, phosphate and alkalinity.

On a happy note- the birdsnest and paly's I got from you are doing fantastic! Thanks Nikki!

[larrynews]

so after looking at some old pictures i think the zoas spread and moved off the plug they were on. i know they have spread so i'm wondering if the others were just stragglers ( the weathering ones)