weird critter

How’s it going! I was recently visiting my local Petco and they were resetting the saltwater tanks. The way they were resetting the tanks was they drained all the salt water out and put nothing but fresh water in and all the unseen cleanup crew and what not started dying and this critterwas in...

I’m currently doing a late night water change on my nano, and therefore all the pumps are off. I noticed one of my berghia nudibranchs was on the wavemaker. No big deal, I’ll just wait until he climbs down. But instead of reaching the wall, he just decided to hover perfectly in place?? Is there...

I have all of a sudden noticed a large amount of white critters on my rock where there’s algae and on my glass when the lights have gone out. I’ve dossed copepods before however they never looked like this ... Any ideas many thanks. please see images below tried to get best images in...