60 Gallon saltwater tank. My first saltwater tank I've had so I'm kind of worried. So 60 gal
saltwater with 110lbs of live rock and 200 lbs of live sand. I've had the sand cycle for about a month and then put in live rock and let that cycle for about a month. After testing repeatedly and receiving good numbers I introduced my first tank mates. 10 hermit crabs of all kinds and two peppermint shrimp. A couple days later I placed in two brittle sea stars (fancy). About a week and a half after that I placed in my six line wrasse. About 3 days after that (3 days ago) I placed in two true percula clown fish and a scooter blenny. EVERYTHING was going perfect. Water numbers were good until yesterday. I woke up and two of the hermit crabs were dead (no shell by body- i have about ten various sized shells laying around the sand-but still no shell on body). I got worried so I tested my water again. Salinity in proper range 1.023, Ammonia is zero, nitrite is zero, and nitrate is about 20 ppm
. I'm fairly certain this wouldn't kill my hermit crabs. So later that day I noticed that one of the two sea stars is starting to lose it's legs. And the other is hiding further back in a whole. Upsetting but the worse is yet to come. Tonight I see my clown fish white as can be and swimming upside down with frayed fins. The other clown has frayed fins as well and is looking like death my soon overcome. But clown fish are super hardy so IDK what is going on. The shrimp and blenny are completely fine, the wrasse looks completely healthy. I drip acclimated both sea stars (maybe not as long as I should have but about 45min-1 hour). I properly acclimated everything but the hermit crabs. I'm feeding very copiously. I have proper lighting, a VERY nice filter, heater and thermometer at about 78 degrees, and a powerhead. IDK what is going on. Could it be the wrasse picking on the clowns and the hermits, all started when I added him and I know they do that. But wouldn't he eat the shrimp too and wouldn't the shell be next to the hermits body's. Also I used tap water to fill up and to top off once ( I know it was dumb it won't happen again- but I conditioned it and placed salt in it) And I used freshwater salt to increasing salinity before realizing it was freshwater salt but we are talking a very small amount. Maybe two spoon fulls. Please help me!!!
Water parameters now:
pH: 8 (low, will get buffer)
Ammonia: .25ppm (has risen since yesteday, probably due to dying fish I can't reach.
Nitrate: 20 ppm
I know these aren't ideal but would this kill sea star, hermit crabs, and a nemo? Without observably effecting shrimp, wrasse, and blenny.