This showed up on a rock out of nowhere. Haven’t added anything to the tank in months, and only cleanup crew and one blenny that disappeared. It’s on the bottom edge of the photo. Greenish centers with feathery edges.
Thanks!
Thanks!
Anyone know what this is?
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hydroid i think.
I agree
Photo is a little bit blurry, but i doubt its hydroid. It looks more like "Yellow Polyps"... similar to palys. They used to be popular a long time ago, but are now uncommon in the hobby.
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They were popular for people who didnt know better.
I dont think these are quite those. But at first glance , thats what i had though too
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Agreed. Why do you lean towards hydroids? ...i just dont see it, but i have open eyes. Also, why do you think these are not yellow polyps?
looks like colonial hydroids to me
For others, who arent familiar with them, here are some google images of yellow polyps. They are known for long wirey tentacles, and come in many shades from brown to bright yellow.
The only evidence that has me suspicious it might be hydroids are the dots on the stems. But its too blurry to tell.
And here is a similar photo of colonial hydroids... also, striking resemblance. But hard for me to be certain from the original photo. ... i think the stems might be key.
The only evidence that has me suspicious it might be hydroids are the dots on the stems. But its too blurry to tell.
And here is a similar photo of colonial hydroids... also, striking resemblance. But hard for me to be certain from the original photo. ... i think the stems might be key.
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Haha... either way, you may want to remove them Nancy. We are just splitting hairs in this convo for the sake of learning. I love learning.
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For me one of my purely anecdotal ID mechanisms for colonial hydroids vs parazoanthus polyps is based around the coloration. Colonial hydroids have a bit of a fluorescent green sheen to their tentacles while your parazoanthus polyps lack this and are just a nice bright yellow.
Looks like hydroids to me in the photo- if it is hydroids, then manual removal, epoxy cover to starve them, use of urchin to eat them, hydrogen peroxide if it is a small area and. It wide spread. Lots of ways to get rid of them before they become a bigger issue.
Awesome @timeconsumer!
Ive definitely seen brownish versions of the yellow polyps. However, you're totally right about the green sheen. Thats a great way to differentiate.
Ive definitely seen brownish versions of the yellow polyps. However, you're totally right about the green sheen. Thats a great way to differentiate.
Wow I did t realize they were that bad. They’re on a rock covered with ricordia mushrooms that I got a year ago. I guess we can remove the rock from the water and manually remove these and put epoxy over that spot I just don’t want to damage my ricordia. Speaking of which, one of the ricordia adjacent to this hydroid thing has turned white, do you think the hydroid did that?
Thank you all for your replies!
Thank you all for your replies!
Thanks Shari, we will take the rock out and deal with it tomorrow
Colonial hydroids. I have some that came in on my FL liverock that im letting hang out. They are not spreading so I've let them have there little 1"x1" patch. Not particularly attractive but these particular ones have not spread.
Yellow polyps ironically are getting tough to find. Took me a few weeks to track them down for my "pest" nano reef along with GSP, Xenia, and Kenya Tree. They spread quick and pack a solid sting, but I'm finding Xenia to be far more invasive.
I believe yellow polyps are more akin to GSP. It will take over a tank if you get lazy but they aren't uncontrollable like Xenia or a Kenya strain that is prone to dropping trees every week. Xenia quintupled in the time it took GSP and Yellow polyps to double.
Yellow polyps ironically are getting tough to find. Took me a few weeks to track them down for my "pest" nano reef along with GSP, Xenia, and Kenya Tree. They spread quick and pack a solid sting, but I'm finding Xenia to be far more invasive.
I believe yellow polyps are more akin to GSP. It will take over a tank if you get lazy but they aren't uncontrollable like Xenia or a Kenya strain that is prone to dropping trees every week. Xenia quintupled in the time it took GSP and Yellow polyps to double.
I've got those hydroids, no the greatest but not the worst type either. They've been in my system for 14+ years and I just knock them back with kalk paste when they get too close to something I like. Removing the rock and scraping hasn't worked for me. The only sure fire way to eliminate a colony is to pull the rock and let it dry. I mean, a few days in the sun dry. They're a pain and their population ebbs and flows but I've never had serious issues with them.
Side note - I had a peppermint shrimp that ate them down to the nub once. They were all gone but once the peppermint pass away, they came back. I've gone through a lot of peppermint's over the years and only ever had a single one that would attack the hydroids.
Side note - I had a peppermint shrimp that ate them down to the nub once. They were all gone but once the peppermint pass away, they came back. I've gone through a lot of peppermint's over the years and only ever had a single one that would attack the hydroids.
Thank you for your feedback. We haven’t done anything with it yet and after the last two responses Matt we’ll just leave it be for now. Worried about harming the mushrooms on the rock and it’s just a small patch. Perhaps when we upgrade the tank we can try to get rid of it
