It's a tricky one to get rid of - the guides I've read about say its to do with the Co2 in the water (even in non-injected tanks) and that it likes high flow. Main thing it advises is to manually remove it, I've been doing it with a kitchen knife but I want to get an aquascaping pick. I know ADA do them which is mega expensive but I have seen them from other brands for reasonable prices, when I keep on top of it and take most of it out it does die off so I think being thorough each session it would eventually eradicate it.
Wills
I'll give it a good go during water change. Flow is quite high in both tanks now but it was in the tank with a dodgy filter and useless flow. Hopefully I can sort it. Thanks for advice