Ca reactor advise

[andestang]

Just getting ready to put my ca reactor on line. Its a dual chamber (mocalc 300/austin oceans) and I've never run one before (always used Kalk) I've been running fresh water through it from a five gallon pail for about four days now(bought it used and the media was left in it for a few months) I get air bubbles that build up at the top of the main chamber and form into a larger one and when it gets to the intake tube that goes down to the pump it of coarse effects the flow and is noisy. I'm worried its going to air lock the pump. I've tried a few times to bleed it out(have a PH probe addapter plug on top), but awhile later more bubbles just form. Any tricks to getting the bubbles from forming on top or is this normal ? I'm also assuming that after the air goes through the pump that most of it will go through the chambers again and won't go out the effluent line.