There are three identifications that I'm looking for help on:

1. This is about the size of a quarter and the only one of its kind in the tank. Friend or foe?

2. I'm pretty sure this is just a giant aiptasia but wanted to confirm. Again, the only one of its kind in the tank.

3. I have no idea what the white 'snow' is on my macro algae. On this red algae the 'snow' looks very white, while in another part of the tank there is more of a mix of white 'snow' and green fuzz. Very small and hard to see from a distance but obvious from the photo or a close-up view of the tank.

Thanks in advance!


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1. Palythoa polyp, not a bad hitchiker but they don't spread as fast as some other colonial type polyps. Which could be good or bad.

2. Yep, aiptasiaish lookin' thing.

3. Hard to say - could be another film algae living on the surface of the macroalgae or if its a calcerous algae the calcium can deposit on the surface of some of these in odd patterns. If its brown and bubbly and looks like snot you may have dinoflaggellates which are kind of bad news - doesn't look like that from your pic.


Experienced Reefer
Ironically, without the aiptasia, I have seen both just yesterday. WISH I had gotten the
polyp as a hitchhiker, but I ordered a rock with a colony. On this rock interspersed with
the polyps is this wide-bladed red algae like your pic 3. I THINK it is a algae, kind of like
a kelp, but I will know more as the days go on. Underneath the algae was what looks like
a yellow porites, so I win. lol. I THINK when I get home tonight, I will know if my yellow
tang finds it palateable.

What I do when I find ONE Aiptasia is I bother it to where it shrinks into it's crevice in
the Live Rock, then wall it in with a ball of pink reef epoxy. It does not expel larvae
and it never is seen again. Sucker.


I've had some success with Joe's Juice -- but this one is at the bottom of the tank and grew so big, so fast, I wanted to be sure that is what it was before "feeding" it. :)



Experienced Reefer
All that is on one rock?? I think I have seen the other piece, lol. I have it.
If not from the same rock, It sure looks like the same zone.

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