seahorse tank/refugium?

[Melina]

Hello,
I've been thinking about plumbing a refugium into my 65g (20g sump) reef set up. I love seahorses and would love to keep them. Would a seahorse tank, (with a deep sand bed, planted with seagrasses & macroalgae), give my reef tank the nutrient-exporting benefits of a refugium? I'm thinking the minimum size for a seahorse tank would be about 30g or so? Is it a good idea to plumb the two tanks together? Has anyone done this?