A friend gave a present of a chinese algae eater, common pleco, fantail, betta, tiger barbs and neon tetras. The algae eater did the first attacks on the fantail and the pleco also attacked. The betta bullied the neons and the barbs bullies the betta. The barbs attacked the fantail too. Can you suggest any distraction fish?

I think the goldfish should be kept in a separate tank from the other fish. It sounds like there should be enough fish that the betta can't pester any one particular fish. In big groups, tiger barbs usually aren't that nippy but the betta would be an easy target. So, you may want to set up the betta in his own small tank or in a divided area in the main tank. Chinese algae eaters, plecos, tiger barbs, and bettas are all potential threats to the fantail so surely move him to his own tank. Did your friend have all these fish in the same tank? How big was his tank, and how big is yours? This is more a situation of incompatibility than one that needs dither fish (distraction fish as you call them). I hope things work out!