critter id

Hey all. Any idea what these are? From other posts it seems like colonial tunicates but I can’t find anything that looks exactly like what I have!!

Hello, so iv been trying to read some other threads and the mixed opinions leave me thinking to post pictures and asking for advice to help best option. 4 yr old 13 gallon tank. No bad stuff in there to my knowledge besides bristle worms. On my back of the tank I have small white tubes, which...

Hello everyone, This tank has been going since 2002 and I keep it mostly natural aside from once a month water changes and feeding. I give it calcium every so often for the stonese. A week ago I noticed this white substance that seems to be around the rocks. It looks almost like bubble gum in...

This guy started out on a rock in refugium, when I went to move the rock into my DT, I popped him off and stuck him to the wall in refugium due to me thinking he was a baby snail. He was about a 4th of the size he is now. This thing has not moved an inch in three months now, but it’s still alive...

I have so many snails in my system. The banded Trochus spawned in the water column when I first added them in spring so there are hundreds. So, I assume these aren't Trochus. How did they get the eggs in the small gap between the cleaner and glass? My rock is filled with baby Nerite, Trochus...

Anyone have any idea what kind of snail or critter this is?

Hello, Are these ball Anenomes? They are all over my reef tank and seem to be bothering my corals and stay open all day. They also attacked a baby hermit, and seem to be really aggressive. Also, any natural predators? (For a 40G tank) Or other alternatives to remove? Thanks in advance!

Anyone know the species ? Saw them walking all over a few mushrooms (these guys are same size as tisbe pods) I also saw them eating dinoflagellates (can only see them under strong magnification) One of the mushrooms was closed for a few days - upon inspection noticed these white bugs crawling...

Just noticed this in my sump this morning. It hasn't moved in the past hour and a half. A friend of mine thinks it is a sponge. Any ideas?

These are in my refugium. Started out with the white one, then a couple weeks later, the bigger brown one formed. Now I’m finding a new brown one about every week or so. They retract if you get near them and they attach to either rocks or the sand. Started seeing these after I put a few pieces...

I have these little guys all along the glass in the sandbed. Have a few in the sump as well. They appear to make their own little cocoon type of thing when there is no sand available. Spotted a couple that are much darker in color, almost black, but couldn't quite get an angle on them to record.

I noticed this little orange-thing while checking out my tank today, thought it was a sponge at first but when I came back to look at it later it was moving and had revealed two little antennas! It only has two colours, orange that fades into a darker orange/brown towards the body, has a clam...

These clear "tube" critters have almost completely taken over the rear chamber of my nano AIO. They're growing and attaching themselves to the glass, heater and temp probes. I've also started to notice them growing on the rock in the tank as well. They seem to soft tissue and not hard, they also...

Never seen one quite like it anyone can ID it came in on live rock rubble it moves , it has two small holes on each end - it is soft and squishy like a slug / snail / anemone and I have seen it squirt once or twice - looking to figure what it is if NPS or a pest or a fish eater Also anyone...

Curious what these are? They look oval shaped and smaller than a grain of rice. Look brownish and move around the glass. Have a V shaped end to the body. Mainly on the glass but probably on the overflow and elsewhere. A good amount of them. Tank has been setup with live sand and live rock from...

I just cleaned a bunch of algae out of my sump and found these critters that look like tiny smooth (no hair or bristles that I can see) caterpillars. I’ve never seen these. In the photos they look flat, but they aren’t. They are nice and chunky. Any help on an ID is appreciated!

Anyone know what these are? They are tiny worm like looking things. I have an idea of what they may be but not positive. Found them inside the skeleton of a dead alveopora… removed it from the tank to detach it from the frag plug it’s on. I try to leave behind coral skeletons in my tank hoping...

Took a sample from my sump and saw this under the microscope. They are clear and pretty fast moving. Any idea what they could be? I have large cell dino in the display. Thanks

Does anyone have an idea of what this is? It’s about 1cm long and moves very fast. Some type of flatworm? I recently received some TBS rubble for my sump.. just want to make sure this isn’t a bad critter.

I just saw a relatively big worm come out from my rock and grab the leftover brine shrimp and then back out to the rock… should I be worried? What is this?

These popped up this morning or well I noticed them this morning, first thought was they are micro brittle stars but also could be some type of worm. I have only a few, fish, common/caribean star, snails, hermits, cleaner shrimp, pistol shrimp. I’ve only used a small piece of live rock from my...

Anyone know what these tiny bug/shrimp looking things are? They are all over this rock and under the coral. Are they good for the tank or are they about to kill everything in sight? Thank you!

Hello everyone, I recently added my first cuc and corals to my tank on the 6th of June (List below). I am running the tank fallow currently and realized that some of the inhabitants need something to eat so I fed some algae wafers, frozen mysis and baby brine shrimp. Emerald crabs Astrae...

Brought a handful of ocean sand to seed my new small 5 Gallon tank. Intentional. Wanted to experiment in a small tank with ocean sand/seeding. Saw these guys running around. Does anyone know what these are? I am planning to set up the tank as an exclusive nem tank. So in essence they will be...

Found this crawling around in my sea urchin. It was flat and looked like a big flatworm. Dropped a bunch of eggs when I dipped the urchin in fresh water to knock it off. Sorry no better pictures.