Hi, I am an newbie and have started a Youngs IPA brew. I thought that fermentation has stopped at 8 days and added hops. However, fermentation started again and I have left it for 5 days now. Just had a look and there continues to be a layer of green foam/slime on the surface. Wondered whether I added hops too soon and should I leave the brew until all the green foam/slime dissipates? Thanks