Emerald crab death after big move

[Jakeroni]

So I am new to the sw hobby, I purchased a somewhat neglected 30gal tank from a lady which contained 2 mature brittle stars, 2 shrimp(either glass or ghost), a sandsifting star, a hermit, a few snails and an emerald crab. When I took over the protein skimmer wasnt working properly for who knows how long, the tank needed a massive clean but everything in the tank is basically what survived the previous owners neglect. When I moved the tank I did what was an approx 50% water change, I cleaned the tank extensively, tore down and fully cleaned the protein skimmer and got it working properly again, I also scrubbed a fair bit of algae off of the rocks before the setup.

The setup went okay but I didnt properly acclimate the critters before putting them into their freshly cleaned home. The water they came out of was a 1.022 salinity and I introduced them to a 1.025 environment.

The first week went really well but on day 6 I found my emerald crab unresponsive. I put him into a container with tank water and prayed for a few hours. He smelled bad, I couldnt see any signs of molting.

I fed them shrimp flakes for the first 2 days and then have been feeding them some frozen shrimp which i thaw in a small cup of tank water. 

I want to know what happened to my little guy, he was seen picking away at the rocks and would even go for the frozen shrimp when he could. My guess is that I over cleaned the rocks and starved him, or if possible the poor acclimation finally got to him? Idk if that can happen a week later. Everything else in the tank seems happy. One brittle star kept climbing the glass but has since calmed down. 

Parameters are as follows: sal 1.025 ph 8.4 cal~400ppm, nitrates below 30 kh read good, I cant remember the exact atm.

[WV Reefer]

1 hour ago, Jakeroni said:

So I am new to the sw hobby, I purchased a somewhat neglected 30gal tank from a lady which contained 2 mature brittle stars, 2 shrimp(either glass or ghost), a sandsifting star, a hermit, a few snails and an emerald crab. When I took over the protein skimmer wasnt working properly for who knows how long, the tank needed a massive clean but everything in the tank is basically what survived the previous owners neglect. When I moved the tank I did what was an approx 50% water change, I cleaned the tank extensively, tore down and fully cleaned the protein skimmer and got it working properly again, I also scrubbed a fair bit of algae off of the rocks before the setup.

The setup went okay but I didnt properly acclimate the critters before putting them into their freshly cleaned home. The water they came out of was a 1.022 salinity and I introduced them to a 1.025 environment.

The first week went really well but on day 6 I found my emerald crab unresponsive. I put him into a container with tank water and prayed for a few hours. He smelled bad, I couldnt see any signs of molting.

I fed them shrimp flakes for the first 2 days and then have been feeding them some frozen shrimp which i thaw in a small cup of tank water. 

I want to know what happened to my little guy, he was seen picking away at the rocks and would even go for the frozen shrimp when he could. My guess is that I over cleaned the rocks and starved him, or if possible the poor acclimation finally got to him? Idk if that can happen a week later. Everything else in the tank seems happy. One brittle star kept climbing the glass but has since calmed down. 

Parameters are as follows: sal 1.025 ph 8.4 cal~400ppm, nitrates below 30 kh read good, I cant remember the exact atm.

Welcome to NR. 😊

 

I wouldn’t beat yourself up over the crab if everything else is ok. He may have died anyway..... it’s really hard to tell with crabs sometimes. 

[Rob22]

Probably just at the end of its lifespan. They only live 2-4 years and there is no telling how old it was when it was originally collected. Whereas they are deemed as “reef safe” and claimed to be herbivores, all crabs are omnivorous. If it was starving it would have taken out one of the shrimps or snails. It also takes a while for something like that to starve. Six days wouldn’t have done it. I have had them take fish that sleep in the rocks as well. Personally I don’t trust any crabs in my tank anymore other than porcelain crabs who are predominately filter feeders.