When you setup your ciss for the first time, you want to purge as much air as possible, it does not have to be completely purged...(a little air in the cartridge is OK)
You will want to set your tank at a height to supply ink effortlessly to the printhead...(not to high and not to low as to start a siphon)
On our HP 8600 ciss there are plugs for maintenance only. (bleed air from the lines on the initial setup)
During normal operation plugs are to be left in...
Check you ink tank, you have to allow your tank to breath, unplug the breather plugs and put in your filters...send a photo of your tank, if you can...
Depending on your chip set, the printer may show your cartridges as empty...click thru the warnings and continue to print...
However if your cartridges are not recognized that is a different matter..(contact your supplier)
Here are the two types of cartridges, one for the ciss, leave the plug in, and the other is a refillable, take the air plug out....