hi,when bought at 1 inch the bn had a pink blotch on its side,it got bigger as fish grew,no other problems with bn for weeks,feeding them tonight it had started to what i can say as eating away flesh of the bn,it was so bad i had to remove it,now can anyone tell what it was and will it hurt the rest,thanks steve47 sorry wrong forum

Photos always help when you need help diagnosing an illness. If you could post some pics then you may get a better diagnosis.

It's possibly a bacterial infection that has become ulcerous and may have been caused by poor water conditions..

You say it was like that when you got it so hopefully if your water is OK then any other fish will be fine but you could treat them with an anti-bacterial like eSHa 2000 to be on the safeside.

Keep the infected fish in isolation, treat it with an anti-bacterial but I would not hold out much hope of recovery.

it has died today,was a mess,other fish moved to new tank.

sorry to hear steve bout ya pleco passing away

Sorry to hear you lost your fish.