I usually detach the tubing to get the air out, and when the water arrive, I attach it back. Kind of messy, but I am paranoid somewhat.
Various gas are always present in water supply, but generally they are very very small amount. I think you just did not bleed the air out completely, and the tends to collect in the lower pressure canister than the ones before the RO. I feel you just need to turn the filter up side down and it will all get out eventually. No need to worry that much.
Hi Robbie - I recently bought a Coralife ro/di and actually read the directions ( figured for $200 bucks I should make sure I don't screw it up) after running it without the DI and the other filter (name escapes me) then I added them and ran it again for like 20 gallons and she was all set to go. I noticed that the DI chamber was nearly full with air so I revisited the directions and it said that air in the chamber is normal. Its been a couple of months and I have made up 100 gallons or so at this point and there is still about 1 inch of air in the chamber.
