Well that the thing. There are going to be natural variety in nature and until someone DNA tests every l number to identify what they actually are then our term for what is a hybrid and what isn't is void. Hypans breed together easily and since they have no or very few predators they will grow in ha...

Mmm if you can find a breeder or aquarist that has what you looking for go for that as he will generally have looked after them better. Sunken belly is quite easy to see though and you should avoid buying these and point it out the seller so he can take care of it.

Mmm the contraden has a solid black tail more likely a small spot variety think it l136 or something like that.

Could be a little swim bladder problem that he is trying to sort out be re equalising his swim bladder buoyancy. I have found live blood worm though even frozen to be an amazing cure for swimbladder problems.

Check your chemistry levels to see if it nitrates are starting to rise.

Well firstly I wouldnt keep ottos with goldfish as ottos are tropical and don't do well in cold water and goldfish don't really do so well in tropical as there body's aren't made for it. So you would find that would be your first problem. To be honest it just looks like a bit of chemical poisoning w...