Thanks for the info. I will watch him closely for the next week and see if it improves. I first noticed it when I was still acclimatising them to the new water/temperature. Just funny how the other two in the same bag were fine. Maybe this one is a wee bit sensitive huh?
My water conditions are good. Ammonia 0, Nitrite 0, Nitrate 5-10 and PH is 6.4. PH is a little low due to Wood and Co2 input I think.
Edit:
Should I perhaps do a couple of extra water changes or would this stress him more maybe?