Forgot to mention it is a 25 litre tank, I know it is small, I am saving to get a new one at the end of the year. Tested the water everything is fine. Tonight I placed one snail and one butterfly pleco back into the main tank, as they had web in te quarantine tank whilst I treated the main one for ich.

I decided I would try taking Brian out of the tank just to see what happened, as soon as I did that he calmed down a bit! So I don't really know what it was all about! 

Yeah I did wonder that but they were all in the main tank roughly 3 weeks ago and there was 2 apple snails, 2 fish and 2 plecos then! He could have grown slightly since then and felt crowded with it! Although I think Roger has grown a little so that might make a difference! Hmmm! It has just really confused me as they were fine all together a few weeks ago!
 I always seem to et crazy animals! Lol!

Maybe you could start hand feeding them and see if that helps?

The goldfish won't immediately feed from your hand it takes a while to get them used to the idea.

The way I went about it was to hold some flakes in between my fingers and dip them in the water. I would hold them there for a while as the flakes soaked and became wet, and eventually they'd fall out of my fingers and the fish would eat it.
Eventually Lucky would come closer and closer to my hand as she associated fingers with food and after a few days of this she was happily nibbling from my fingers, in fact now she nibbles my fingers checking for food when ever I'm doing things in the tank

With feeding extra food, if it helps, then that's good, but I would agree with testing the water more often whilst doing this, just in case