just filled tank with water,,,instructions say fill to above water level line on tank..I/We can not see a water level line on tank,,how high do you fill tank with water????? have filled to glass and black top meeting is this correct. Everything is turned on and look/working great but getting large air pockets occasionally,, is tat surposed to happen,,or should the flow be more steady/fluient :dunno: ,,,any help at all be great..Cheers again. :dunno: