He is no longer upside down, has crept into a rock crevice and is half poking out / half hiding.
Yes I use RO
water, parameters in tank stable for about 6 months now (it's just over 8 months old). As for lighting- my tank has a hood, the lights are 2x 18w T5 10,000k lighting.... If that means anything?!
Might try and feed him later today, person in fish shop sold me a bag of frozen fish (each about an inch long) and told me to feed it half a fish every couple of days . Not sure how to get it to him- tweezers??! Alternatively was going to squirt some brineshrimp towards him using a syringe?
Will try get a photo once he is less hidden .