I want to make a refugium from a 30 gallon tank for a 55 gallon tank. This picture i drew is to scale. every 2mm is 1 inch. yea i mixed metric and standard but i dont care. Are there any flaws with this design?
The way you have it outlined now you have the water flowing into the bottom of the refugium chamber when it should enter at mid level or higher, assuming the 11" section is where you want macro algae and stuff.
you need about 4-6" height dividers for the mud/sand and it shouldn't get disturbed too much by the water flow.