Found these on my glass

[Wbartsch]

Ent out for the weekend. Came back to 4 or 5 of these guys on my class. Theyre about a millimeter long tops. Anyone know what they are?

 

[manbeast]

I've been told they're flatworms, had some in my sump once and they seem to have disappeared on their own, but mine were transparent with no pigmentation at all, I have heard that there are some that may feed on corals but really don't have much experience with them hopefully someone with more knowledge will chow in

 

[Deuce788]

I had a run in with flat worms you have to be careful if it is flat worms when they die they release a bad toxin into your tank and it can kill your fish. Take a turkey baster and suck as many as you can out then use flat worm exit to kill the rest off if there's one then there are a lot more that you can't see. It will take time to get rid of them but you want them gone as soon as possible they multiple fast

 

[bribo12]

I had a run in with flat worms you have to be careful if it is flat worms when they die they release a bad toxin into your tank and it can kill your fish. Take a turkey baster and suck as many as you can out then use flat worm exit to kill the rest off if there's one then there are a lot more that you can't see. It will take time to get rid of them but you want them gone as soon as possible they multiple fast

Only the aceol flatworms do that when they die. Aka the bad ones that eat acropora. The one above appears to be the harmless algae eating kind. I'd just leave him be.

 

[Wbartsch]

Well i dont have any acros. If he just eats algae thats fine with me! I sucked two off the glass today i havent seen any of the tan ones around. If i do get an acro eventually will it be safe? How can i make sure that no more of these guys get in? And is that chemical solutuon reef safe? Sorry for all the questions. Only been doing salt water for about 4 months. Relativly new

 

[bribo12]

Well i dont have any acros. If he just eats algae thats fine with me! I sucked two off the glass today i havent seen any of the tan ones around. If i do get an acro eventually will it be safe? How can i make sure that no more of these guys get in? And is that chemical solutuon reef safe? Sorry for all the questions. Only been doing salt water for about 4 months. Relativly new

You should be fine. Those appear to big to be the acro eating species and you have no acros so it will die off if that's what it eats. I'd leave them be they are harmless IMO. Any acros you get should be fine. The flatworm exit is reef safe but no need to use it.

 

[mr_X]

That's common red planaria. They are ambush hunters and also get nutrition from light. These are the ones that like to perch on corals in mass numbers and block the light from getting to them. They do no purposeful damage like feeding on the coral, but in some extreme cases, they can cover them and stress them.
Their populations rise and fall for no apparent reason, other than their main food source (pods) is depleted.
I would vacuum them out and use the flatworm exit, if they are in the DT.

 

[Wbartsch]

Heres a picture of one on my rock from the top

 

[mr_X]

Your first picture is awesome btw. It shows the apparatus it uses to catch tiny inverts.

 

[mr_X]

BTW, check this out-
https://sites.google.com/site/macropyga/
open the pdf files too.

 

[Wbartsch]

So these guys are definitely bad?

 

[mr_X]

I wouldn't say they are bad. I have some in one of my sumps right now and do nothing to eradicate them. They can become a bit of a nuisance though. It's better to wipe them out when they are a small population, if you are going that way.