Adding Sugar Sand to an established DSB

[ldzielak]

In my refugium I want to add 30lbs of aragonite sugar sand to the existing reef sand. The existing sand has been arround for a year and survived the move in Oct. So how do I add all this extra sand without killing all the critters? Should the fine sugar sand be on top or on the bottom. Can I do this all at once by shutting the refugium/sump down for a few hours.

This sugar sand was in my FO tank for the past 3 weeks, before I removed it in favour of a larger grade of sand. It has good bacterial coverage and does not float and make the water like milk like it first did.

I'm thinking of pushing the existing sand to one side and filing the other side with the sugar sand and then slowly over time mix them together.