I'm scared of the answer

[Dondante]

They are on another green leather. Also had a birds nest and two stick colonies turn for the worst.

 

[Robert Binz]

Looks like flat forms and the way they’re all over the leather looks like they’re eating it

 

[JumboShrimp]

If it makes you feel any better, loved the title of your thread ;Playful

 

[Fishy212]

Looks like nudis. Do they appear to be more more wavy around the edges? Could be soft coral eating nudibranchs.

 

[Beefyreefy]

They appear to be red planaria flatworms. They are basically harmless but can become so overpopulated that they irritate or block light from reaching coral. You can spend a little time every night sucking them out manually with a small airline hose. I tie a media bag to the end of the hose so that you catch the flatworms and then can dump the water back in the tank. When you get down to almost none left you can finish them off with flatworm exit. I would only use flatworm exit when they are almost gone because a huge die off of flatworms can nuke a tank.

 

[Flippers4pups]

They appear to be red planaria flatworms. They are basically harmless but can become so overpopulated that they irritate or block light from reaching coral. You can spend a little time every night sucking them out manually with a small airline hose. I tie a media bag to the end of the hose so that you catch the flatworms and then can dump the water back in the tank. When you get down to almost none left you can finish them off with flatworm exit. I would only use flatworm exit when they are almost gone because a huge die off of flatworms can nuke a tank.

This^.

 

[Dondante]

Looks like I've got my work cut out for me.

 

[Sosuke]

I got flatworms too just realized yesterday and purchased a mandarin in hopes of it to eat them. But of course the only coral damaged had to be my RR angry birds ;Facepalm

 

[Phycodurus]

+1 on the mandarin, but ascertain you’ll have a healthy copepod population to supplement the mandarin’s diet while also encouraging it to feed on other prepared foods. you may not get an individual predisposed to picking off the flatworms.

i tried to address a red planaria outbreak in my main 180G tank on two occasions with blue velvet nudibranchs, but the nudibranchs always seemed to disappear within a week.

i later found out that spotted mandarins will feed on red planaria (and i have one in the tank). not sure if the flatworm population explosion eventually petered out, or if the spotted mandarin consistently snacked on the red planaria, but i still have one very fat & happy spotted mandarin.