What is this!?

KeMiKiLL · Mar 25, 2021

Yesterday I added a few frags to my pico and things have been going great. They were dipped, rinsed 3 times, then added to the tank. All are fully open today.

Then I see this...

This is zoomed in pretty good and I'm surprised at how clear it is, but this is one of the largest ones at a little over 1 mm long. There are dozens on the glass that are about half the size.

I've never seen these so they must have survived a 15 minute Coral RX Pro bath. Should I be worried? What are they?

reefer024 · Mar 25, 2021

Do they kinda like skip/click on the glass?

JohnTheReefer · Mar 25, 2021

That is a flatworm.

reefer024 · Mar 25, 2021

Well that is no good if it's a flat worm. They will over take your coral

lelandmarine · Mar 25, 2021

Agree flatworm, see link below

https://www.reef2reef.com/ams/flatworms-the-good-the-bad-and-the-pretty-terrifying-part-1.530/

JohnTheReefer · Mar 25, 2021

reefer024 said:
Well that is no good if it's a flat worm. They will over take your coral

If its an Acoel it is not harmful to coral. Acoels eat small pods and related things. If it a red planaria then there is a possible issue.

reefer024 · Mar 25, 2021

JohnTheReefer said:
If its an Acoel it is not harmful to coral. Acoels eat small pods and related things. If it a red planaria then there is a possible issue.

Good to know

KeMiKiLL · Mar 25, 2021

JohnTheReefer said:
That is a flatworm.

I just Googled this and you are right. They aren't "rust colored" yet, but definitely the exact shape.

This is in a 5 gallon tank with no fish. Do you think a dose of Flatworm eXit would be safe?

KeMiKiLL · Mar 25, 2021

JohnTheReefer said:
If its an Acoel it is not harmful to coral. Acoels eat small pods and related things. If it a red planaria then there is a possible issue.

Just Google these too and they look the same also. These ones are all white but the horseshoe head shape with two "tails" seems common between Acoel and the red planaria...

JohnTheReefer · Mar 25, 2021

KeMiKiLL said:
I just Googled this and you are right. They aren't "rust colored" yet, but definitely the exact shape.

This is in a 5 glow tank with no fish. Do you think a dose of Flatworm eXit would be safe?

I've never used flatwormX in a pico due to fear of not getting the dosage correct for a small volume of water, but I've gotten rid of some flatworms by simply cleaning the glass with a magnetic algae scraper. What corals are you keeping in the pico?

JohnTheReefer · Mar 25, 2021

KeMiKiLL said:
Just Google these too and they look the same also. These ones are all white but the horseshoe head shape with two "tails" seems common between Acoel and the red planaria...

Yes, they do closely resemble each other. The color is mostly how to tell the difference.

KeMiKiLL · Mar 25, 2021

JohnTheReefer said:
I've never used flatwormX in a pico due to fear of not getting the dosage correct for a small volume of water, but I've gotten rid of some flatworms by simply cleaning the glass with a magnetic algae scraper. What corals are you keeping in the pico?

All LPS and softies. Zoas, polyps, GSP, Xania, a hammer and a frogspawn.

monkeyCmonkeyDo · Mar 25, 2021

Clear ones are fine and a beneficial hitchhiker or addition. Micro critter.
D

JohnTheReefer · Mar 25, 2021

KeMiKiLL said:
All LPS and softies. Zoas, polyps, GSP, Xania, a hammer and a frogspawn.

IME, I would not be too concerned if they are not red planaria. Flatworms can multiply quickly. Acoels can crawl on soft corals and LPS without harming them. They are most likely looking for food that is on the coral not the coral itself.

KeMiKiLL · Mar 25, 2021

monkeyCmonkeyDo said:
Clear ones are fine and a beneficial hitchhiker or addition. Micro critter.
D

Okay. So I shouldn't be worried unless these guys turn red?

JohnTheReefer · Mar 25, 2021

KeMiKiLL said:
Okay. So I shouldn't be worried unless these guys turn red?

Correct, but keep us posted if they do!

KeMiKiLL · Mar 25, 2021

JohnTheReefer said:
Correct, but keep us posted if they do!

Will do. Thanks!

LegendaryCG · Mar 25, 2021

Flatworm... wrasse will eat it or there’s flatworm stop if you have SPS variety. If you see it just grab it and remove it, we over think problems a lot.

vetteguy53081 · Mar 25, 2021

These are not of harm, HOWEVER can be a nuisance when in numbers as they favor the stem of coral and will block the light needed for production of zooxanthele which are building blocks for coral.
Simply siphon them out with a 3/8" or 1/4" tube or utilize a wrasse if in large numbers such as : Coris, 6 lined, lunare or melanurus.
I avoid treatments such as salifert flatworm exit. Although it works well, you must siphon the dead ones a few times daily as they can release toxins into the tank.

KeMiKiLL · Mar 25, 2021

JohnTheReefer said:
Correct, but keep us posted if they do!

Just took a closer look and found a few red ones! Since these had to have come in last night with these new corals, I'll hit the tank tomorrow with eXit. I used a small pipette and sucked all of the ones I could find off the glass.
From what I'm reading, eXit is harmless but the toxins released by these little guys when they die is what can cause issues. Might as well get them while their numbers are low. I'll run extra carbon and do a water change a day later. It looks like eXit treatment has to be done a few times to catch stragglers.