Mining with RX 480 4gb. How should I go about it?

My rig is using an RX 480 4gb. I want to mine raven and am not sure what the best miner and pool is for this card. I am currently using 2miner pool with Team Red Miner. I am wondering if there is a better option to either of these for the RX 480? Also, my GPU was going at 22 MH/s yesterday but is now running at 7 MH/s. Is this normal to see this fluctuation? Thanks