Digital BW, The Print

I just tried filling carts for the first time... but I'm not so sure
it was a success. I filled the carts with syringes as directed and
left them alone overnight (about 18 hours, actually). The black cart
looks fine, but in the color cart, there are visible air pockets
(almost 1 cm in diameter) near the exit ports of the yellow and
magenta tank. I'm using the MIS UT-FS inkset in virgin empty
(sponge-type, not spongeless) carts for an Epson 1160.

I called MIS tech support, and they suggested I try using the syringe
to remove ink and see if it was foamy -- then to replace the foamy ink
with fresh ink and start over. But the ink wasn't foamy. For some
reason I wasn't getting the air pocket when I tried extracting ink.

So -- any suggestions? Can I start printing, despite the air pockets?
Should I add more ink? Do I need to start over?

Any help would be most gratefully appreciated.

Peter