To clarify, I don't really know if it WAS him who pushed the screen out of place... He jumped out shortly before a goby did, and the screen wasn't on the floor; i had went to sleep, woke up, couldn't find the pipefish, thought he was hiding, went back to sleep, woke up due to a splash, saw a pipefish on the top, but looked as if he had been there at least a night (repulsive, I know...) which was depressing, too, but saw the goby was still in his hole. So, that being said, the only conclusion that I can come to is that the pipefish jumped through the screen, and when I didn't look at the top, died. A short while later, I awoke because the rose goby jumped and went down into his burrow again, prob startled because someone honked a horn outside or something. Finally, found pipefish and gave em a final farewell, before drifting off to sleep again. When I finally awoke, in the morning, the rose prob jumped again w/ enough force to jar the lid and pass away. Problem solved.
All parameters have been, and were, perfect. Now the banded pipefish is fine with the only other fish being a baby sail blenny. Welp, see you all later.