Tank Mates Dying :(

[cab_heat]

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:
Salinity: 1.024
pH: 8 (low, will get buffer)
Ammonia: .25ppm (has risen since yesteday, probably due to dying fish I can't reach.
Nitrite: 0ppm
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.

 

[Riverhawk]

Ok..#1: if feeding copiuosly..means too much..I feed my guys(10&8 gal nanos) 2x week..
#2: NEVER use tap to top off...use ro or distilled..add no salt..salt doesnt leave tank only water leaves on evaporation..adding salt to tp off will cause a salinity spike which can burn your critters..this could be why clowns are or were like they were..as for hermits..maybe vics of salinity spike to or their buddies took them out... They do do that....

 

[Riverhawk]

Also need to do pwc on tank..trates may be touch high.... On a 60 gal should have 2 power heads at opposing ends,if possible... This helps your ph and gas xchange..

 

[cab_heat]

Ok..#1: if feeding copiuosly..means too much..I feed my guys(10&8 gal nanos) 2x week..
#2: NEVER use tap to top off...use ro or distilled..add no salt..salt doesnt leave tank only water leaves on evaporation..adding salt to tp off will cause a salinity spike which can burn your critters..this could be why clowns are or were like they were..as for hermits..maybe vics of salinity spike to or their buddies took them out... They do do that....

Yeah I feed a pinch of flakes a day.
Frozen meat by the half a cube 3 times a week.
and a quarter of a silverside to both sea stars three times a week.
I don't think that is too dramatic... Is it???

And the only reason I added salt was because the salinity was low. It was about 1.022 so I added literally a spoon full maybe two to get it to 1.024.

And I intend on doing a PWC tonight of about 18 gallons with RO water form LFS.

I will get powerhead soon. More or less important that protein skinner?

Any other possibilities or recommendations.

 

[cab_heat]

New update

2 more hermit deaths. I got to watch them fight over a shell What I don't get is I purchased 10 at LFS and they are all around them as they fight to the death. And what is even more sad as an assortment of 16 is literally in the mail on the way to my house.

Second clown is on it's last breath. The frayed fins got worse, the fish is pale and starting to struggle.

Also, the wrasse will not come out of a whole. (typically super active)

I'm noticing white things ALL over the glass. Circular with hairs coming off of them. Is this white algae? Or some minute "critter?" Could this be causing it all?

What is going on!?!?! I did everything right to a tee (other a 2 gallon top off with conditioned tap water)

Shrimp are fine and my sea stars look even better than the were?
I was so excited to get my tank looking good and this is what is happening? ((

 

[54seaweed]

I think I see your problem
first off never add unmixed salt straight to your tank with live stock in there
you should always premix before adding saltwater it makes it a bit more stable IMO
just dumping salt in your tank with inhabitants is just asking for trouble
hermits will kill each other off thats normal
but as you said fish fins were frayed most likely from salt poison in other words salt burn
don't think it is ick in this case

 

[forzaazzurri]

New update

2 more hermit deaths. I got to watch them fight over a shell What I don't get is I purchased 10 at LFS and they are all around them as they fight to the death. And what is even more sad as an assortment of 16 is literally in the mail on the way to my house.

Second clown is on it's last breath. The frayed fins got worse, the fish is pale and starting to struggle.

Also, the wrasse will not come out of a whole. (typically super active)

I'm noticing white things ALL over the glass. Circular with hairs coming off of them. Is this white algae? Or some minute "critter?" Could this be causing it all?

What is going on!?!?! I did everything right to a tee (other a 2 gallon top off with conditioned tap water)

Shrimp are fine and my sea stars look even better than the were?
I was so excited to get my tank looking good and this is what is happening? ((

I've kept freshwater tanks for over 30 years and never had an ick problem.
I started my first saltwater tank this year and the tank became infested with ick to the point I had to remove all the fish and will keep it fallow for at least 6 weeks. I've never had a fish jump during my freshwater days and I've already lost a jumping fish this year. Before the ick problem some fish were disappearing and presumed dead.

What I'm trying to say is don't get frustrated and keep trying as these fish loses are all part of learning. I'm going to reload and try again and will do things different this time. All the reading in the world won't prepare you for real life experience keeping saltwater tanks.