critter

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...

Anyone know what this is? LFS owner and I have been watching it for a week and have no idea, when it open fully, it gets out about an extra quarter inch. No tentacles or anything. It also reacts and will retract when touched

Hello, Can anyone ID this critter I found swimming in my tank earlier. I caught one to see if I could get a better view, but there were quite a bit.

Coral Only tank, no fish/inverts. Any idea what this little tentacle is? I recorded one of them but I see 2 short ones and 1 slightly longer one. If a pest, any advice on how to remove it?

I got a good deal on some live rock from a gentleman on Facebook probably about 50 lb for about 80 bucks. The rock looks good supposedly he was storing it in a container with a powerhead and heater I don't know if I believe the heater part but besides that The Rock is definitely covered in...

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?

So I picked up some extra shells from the Lfs for my red legged hermit to give him some options to live in and when I threw this one in to my surprise some legs popped out… anyone know what type he his?? Black legs with yellow spots and yellow claws??? Got such a fright when I seen him come out...

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!

Curious as to what all these different critters growing on live rock in my NPS tank are? I know some are sponges but I’ve included pics of a few I’m not sure of. I’ve seen most of it here and there before but I feed my NPS tank consistently so I’ve noticed new growths popping up everywhere on my...

Hi I have noticed these strange critters. Almost look like little flatworms but move like copepods they are dark red towards black to look at under blue lights. I think they are causing some tissue recession at the base of my acros and my candy cane coral? Or they may not be a pest and the...

Hi everyone, I was just looking in my tank with a flashlight when I saw a couple of unknown isopods crawling around my Zoanthid coral, these isopods seemed to be eating away at the fragplug. I went to google to see if they were harmful since i’ve never seen them before and I only came across...

So usually I never really pay close attention to anything in my refugium, all i do is get rid of some seagrape and Chaeto that have grown to an extent where it blocks off the top view of the refugium. This time after resetting up my dosing pump, i realized this weird creature hanging on the side...

I found this little creature crawling on my glass at night, and I believe they’re flatworms. Can anyone help ID this? Or at least tell if they’re harmful or not? It looks transparent/white with black dots on them. Doesn’t look like brown flatworm unless it’s a baby.

This is my first tank and I have been keeping it for almost 1.5 years. I have no idea what these small black polyps are that are growing like crazy. They seem to be a small fast-growing coral that closes when I touch it. My LFS told me to basically perform surgery and get the zoas off that...

Hello All. New to the hobby and the tank is new (3-4 months Old now) i was just sitting there checking everything over and noticed this bug with wings sat in my return pump section of the sump. To me it looks like a fly as it looks like it has wings but it is submerged under the water and has...

Just though this was cool, recently got some female emerald crabs from reef cleaners in hopes of tackling a moderate BA outbreak (even though nitro is undetectable) , they have completely ignored the Bubble Algae … One of the emerald crabs kept going to an area in the rocks and eating some sort...

Hey everyone! Back again with another critter ID! Found this clam-like critter on one of the shells that this hermit has been carrying around for a while At first I figured it was just some sort of abnormal growth from the snail that used to call this shell home. I noticed recently that this...

Found little isopod-looking guys in my Chaeto as well as on my live rock. They seem to come out at night. They look too big to be copepods... so what are they? Should I be worried?

. White object under my rock fluffy looking

Got new corals, dipped them properly and i’ve just seen this right now at night. Any ideas what it is and if it’s bad ? looks like a starfish or something similar. quite small and white and pink/ red bands ?

I was cleaning my glass and noticed an abundance of these small Star like critters on my glass. They’re tiny - like a thin point to a lead pencil. To my eye they look like 4 pointed or Star shaped, but my phone was able to take a pretty detailed photo. Here are two different ones. ‍♂️ curious...

There is something semi transparent under one of my zoanthids, anybody know what it is

Hello! I run a 5 gallon PICO tank that until yesterday had no fish. I also feed phyto daily, so there has always been an abundance of wee beasties that have fascinated me. Most I've been able to identify (copepods, amphipods, munnid isopods, spinoid worms, spirorbid worms). However, there have...

Sorry for the bad pictures. It’s i. My fluval 13.5 and I didn’t scrape off the back side of it. You can kind of see it but they look like white webs all over the chamber in the back. Looks as if they’re keeping the chamber clean of detritus in the first one but the second chamber is a little...