I am new to saltwater tanks and realize I have a lot to learn. I have a 40 gallon tank with live sand, live rock and base rock. Tank has been set up for about 2 months, no fish yet, been letting tank cycle. I believe by the water parameters that it is ready for fish but I have a couple of issues I would like to address before I put fish in. One problem I have is aiptasia anemones have already blessed my tank, if anyone knows of a good remedy for these it would be greatly appreciated. The other is some little white circular creatures just started appearing. They have tentacles, like to stick themselves to the glass and swim like jellyfish. Don't know if they are good or bad. I have included a pic of them, there are 3 in the pic, one is almost center, one looks like a white dot on the power head, and the other is top left. If anyone could help me identity these it would be a great help.