I've got a 29 with a 10 gallon refugium. I run an Aqua C Remora in the main along with two small powerheads along the back wall. The feed into the main tank comes from a MAG 5 and I figure runs about 300GPH into the tank. I've got a pair of seahorse, a pair of small clowns, a hectors goby, six line wrasse, been running for just under a year with no problems. The seahorse don't seem to mind at all and do just fine. Probably more current than optimal for them but they dance all over the tank and change colors all the time so they seem happy.