It's one of these guys. For an HP. Different than the more cube shaped ones. The bottom is an open circular opening with a sponge. I don't have an adapter to put a syringe on it to suck the ink through as you can do with the other cartridges but while refilling it the ink went through so it's full and open. I run a pic of all black to push the ink out and get barely any ink. Is the circuitry broken maybe? What's the trick here if any?