Red volitan lionfish on hunger strike?

[YankyTexan]

OBSERVATION: our 4" red volitan lionfish has not eaten in 4+ days. Approaches mysis shrimp at feeding time and then swims away. Refuses small pieces of shrimp when offered on a feeding stick.

BACKGROUND: has been living in a 150g FOWLR with a similar sized porcupine puffer for 3 months. It has grown approx. 1" during this time. Normally feeds vigorously daily. Weekly 10% RO water changes. One cube of mysis shrimp is fed daily. Tank test readings are as follows:
SG 1.0235
Temp 78 deg
Ph 8.0
Amonia 0.0 ppm
Nitrites 0.0 ppm
Nitrates 5-10 ppm
Calcium 430 ppm
Test kit manufactured by API
Above readings are consistent with results during the last several months.
All other tank inhabitants are feeding/acting in a normal manner.

Is the red volitan's "hunger strike" something to be concerned about? What would be reasonable next step(s)?

Thank you in advance for your interest and advice.

[snommisbor]

4 days is not too bad, but I had my v. lion that was eating out of my hand and suddenly stopped eating. I did water changes about every 10 days and water params were good especially since I had more delicate fish and a starfish in there that were fine. He stayed fat but I never saw him eat. I bought 11 chromis was down to 6 yet I never saw him actually eat them, anyway he finally died after about 2 1/2 months of this. That was about 5 weeks ago, my chromis have remained at 6 and school real nice so I am sure he ate the others. They say if you put some live ghost shrimp in there and he doesnt go after that then he doesnt feel well, but like I said 4 days is nothing so don't get too upset right now just monitor him.