Snowflake eel dying. Help!

[One fish]

My snowflake eel (Colonel Slithers) has been giving me concern the past week. He hasn't ate anything in a bout 4 days.
At first I thought he was stuck or crushed under my base rock. He has a cave down there that he tunnels out. He clears the sand out and then the rock settles and sinks down over the next week. He then wiggles and throws sand out again, the rock settles, etc.
Today he just came out, but he is super pale. Sort of a milky white like a ghost and early black. and i tried to feed him but he won't eat. Is he tired of eating raw shrimp? is he sick? is he dying?
Any help would be appreciate or anybody that has a snowflake.

[Dundermifflin]

I've always had snowflakes. I changed from shrimp to krill and feed with a wand directly and was successful. Only issues I've had are incompatible fish (wrasse and even damsels) and water temp going too high when chiller wasn't working. You want to make sure your salinity, temp and waterflow are where they need to be. Also, are there any fish that are nipping at the snowflake?

[One fish]

Nobody picks on him. He's bigger than my other fiah. The temp stays around 78 to 80 with the halides on. I use a feeding stick he has always taken it in the past. The problem I have now is not how to feed him but just he's not taking it.