Hydroid or Algae?

2farNorth

In Memoriam
Hi there! Well I have this nasty 'stuff' growing very rapidly in my tank... I was looking for a ID of an Algae in a couple other Forums, but I had a couple suggestions that it may be a form of Hydroid... Any Ideas? and if so,,, any thoughts of how to get rid of it?


PinkPurpleAlgae.jpg
 
Yup, Hydroids, and as far as I know, the only reliable method to get rid of them, or at least keep them under control is by manualy scrubbing / scraping them off of their substrates. They do look nice though.

Chuck
 
Ok, here are a couple new photos, This is about as close up as I can get without losing patience :mad:

Out of the tank of course..

Hydroid1.jpg


Hydroid2.jpg


Hydroid3.jpg
 
Now I'm just confused, in your previous photos, it appeared that the tips of the "thing" had tiny extended tentacles. Which is why I thought of hydroids. But now, in these photos, it appears to be very much like a macro algae. When you removed it, did it break off easily? or did it take some effort and came away more in a tearing? I guess you would be best at figuring it out. If the tips extend tentacles, then its a hydroid. If they do not, then its a macro algae. Sorry for the confussion.

Chuck
 
The last pictures are of it out of the water, the 'fuzzy' ends retract,,

They pull out fairly easy... actually some just pop off, others tear off... but the first pictures in the post, are how they look in the tank....
 
Fuzzy ends retracting would make it a hydroid. If you wish to remove them, about all you can do is to scrape them off of the rock at their base. Personaly, I think they look good and would want to keep a bit of it if they are not going to endanger other animals.

Chuck
 
I agree, they did look good at first, but within a week, they were everywhere, and now they are starting to cover other algae (Sargassum, etc.) snails, pretty much everything except for the corals and fish..

I guess all I can do is keep pulling them out for now...... for some reason they are not in the fuge yet.....

If it was just a couple spots affected, I think it would be an interesting addition, but you can barely see the rock....

I think I'm going to get my prop tank up and running sooner then planned, just incase I have to take drastic measures.
 
I found your dilemma to be a challenging one so I began think of what I would do in your situation so here is a "drastic" measure you may want to consider. Its really not as drastic as you might think. What I propose would probably yield faster results than cooking your rock with a lower probability that the hydroids would return.

Judging from your infestation and lack of enjoyment from your situation I would try removing all your corals from the infested rocks and let the LR dry out in the bright sun a day or two. This in turn should be enough to kill off all the highly water dependent surface dwelling hydroids. You can collect various worms and critters that will abandon the rock during the early stages of drying. Of course you would want to do this indoors near a window or in a sun room if possible this time of year.

After sun baking you can swish the rocks in some SW and remove excessive die-off with a wet toothbrush. Plenty of spores and encapsulated organisms inside your rock can survive this process. Even feather dusters, bristle, and peanut worms can survive this if done by keeping the surrounding air temp above 73 degrees or more. You would definitely be on your way to some nice LR a few weeks sooner than if you were to cook it. I would hate to see you cook the rock just to see the hydroids reappear again which would be very likely IMO. During the night you could cover the rocks with plastic to keep the temp stable. Plenty of pockets of water will remain inside the deeper parts of the rock.

Back in my collecting days in FL I was allowed to take rocks washed up on the beach. Many of these rocks were dryed out for days. All of them had feather dusters and other things appearing within a few weeks of placing them in my tanks.

I know this may sound unconventional but with this method you are utilizing nature to do the work for you without killing everything on your rock. You would be surprised how much life would come back in just a month or 2.
 
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Actually that is an alga. If I saw that off California I'd call it genus Laurencia but there could be similar tropical algae in different genera. One of the characters for this group is the cluster of small hairs at the growing tips. Out of water the hairs seem to retract but they're clinging to the sides due to water tension.
 
I hope you are right even though I devoted plenty of time thinking it was a hydroid and trying to think up with a way to erradicate it. It was the cluster of small hairs at the growing tips and its rapid growth that had me convinced it was a hydroid of sorts.
 
A lot of fish and inverts won't eat Laurencia. These algal species produce a wide variety of defensive chemicals that protect them from herbivores. On the other hand some animals like sea hares selectively eat Laurencia; it's suspected that the sea hares are incorporating the algae's secondary metabolites into their own defensive systems.
 
It's growing in the 90, so far I'm able to keep it out of the 38, I had another reefer that I was going to give a ball of chaeto to that I had in quarentine, but after closer inspection I noticed it too had a couple branches intertwined within, good thing I cought that!!!!

This stuff is actually a good nutrient exporter, all my chaeto in my fuge is actually dieing off, I didn't have much to start with... now of course when I feed, (frozen) it looks as if there is so much of this algae in the display, that it traps some particles fairly easy... and of course it's next to impossible to get to it because of the type of rock... soooo, I'm probably feeding it every time I feed the fish....

Actually my LMB does pick at it,,, he may just trying to get at stuff underneath, hard to tell.. either way, he don't help the problem,, he tends to spread it out more <L>

I'm still looking at ways to start a prop/another system so I can move the fish/inverts from the tank, and start to eradicate....
 
Well guys, I think it's official, I am losing the battle!! The more I pull, the more it comes back... not sure if there is an end in site!!

So, next step is drastic... pull all the fish, inverts, corals and such out, put them in a temp. 55g, with some of the infected LR, And start over....

I was planning on upgrading to a 120 down the road, well now I guess it will be sooner then I thought!! Hopefully I'll get to meet you 'Spike' (planning on getting my tank from the new store).

And hopefully I'll be able to get everything up and running by June, (going to F&S Coral Conference).. Should be able to.. planning on all new LR, upgraded skimmer/sump/fuge.. the whole 9 yards,,, and a decent quarantine system for corals... (any tips would be greatly appreciated!)

Then I can take my time and find out what actually kills this stuff... It's too nice of rock (Pukani) to just through out, so that means I'll probably set up another tank down the road!!

Thanks for all the help!! And Leslie, it does look almost identical to Laurencia... Either way.. I'm still going to do more research on what it actually is, because trust me noone wants this in their tanks!!!
 
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