Hi all,
So I'm planning to make a removable 20 gallon external refugium for my 120. My tank doesn't have an additional area for fuge in the sump. My plan was to drill 2 holes offset into a 20 gallon tank positioned a bit higher than My sump, then to pump water up into the 20gal to gravity flow back into the sump return area. I have attached a schematic. The fuge will run with a kessil h80 and be lined with some rubble rock and hopefully rolling chaeto.
My main question is how dumb is this, and what size holes to make. I know I'll need to seal it with silicone and use a baffle. Any comment is helpful!

So I'm planning to make a removable 20 gallon external refugium for my 120. My tank doesn't have an additional area for fuge in the sump. My plan was to drill 2 holes offset into a 20 gallon tank positioned a bit higher than My sump, then to pump water up into the 20gal to gravity flow back into the sump return area. I have attached a schematic. The fuge will run with a kessil h80 and be lined with some rubble rock and hopefully rolling chaeto.
My main question is how dumb is this, and what size holes to make. I know I'll need to seal it with silicone and use a baffle. Any comment is helpful!




