I have had a few different types of pipefish in the tank with the seahorses with no problem about competing for food, other than the fact that the pipefishes seemed to live off the 'pods, and when the seahorses are hungry and your not feeding them at that moment (which is all but what, 20 min a day? lol) they're scouring for pods too... I have 11 seahorses and a mandarin as well, and they do fine, but both types of pipefish I've tried (the ones like yours, mystery, and also the red-banded ones) have only lasted a few months before they mysteriously died, though I assume from malnutrition. I never saw any of them eat anything other than copepods, so maybe that was the problem, but as far as compatability for a seahorse tank.. they make excellent tankmates imo.