For serious fish producers.
Most of the solids settle on the bottom of round tanks, so why not use the tank as a solids concentrator? We designed this drain to do just that! It splits tank discharge into two pipes: a small volume (5–20%) waste line and a main drain (80–95%). The main drain can go to a high rate polisher or straight to a biofilter. The waste line can go directly either to waste discharge or to a miniature clarifier. Miniature because it takes less than 20% of what it would have to handle if it weren't already separated. The waste line can operate continuously or intermittently on a timer.
The body of our double drain is hand-laid fiberglass containing two 4" slip PVC connections for easy access (the size can be reduced at any point). The retaining plate and fasteners are 316 stainless steel and the 4" x 11" removable grate is fiber-reinforced plastic. All saltwater compatible. The main drain can be used with a standpipe, a mid-level inlet or even a pivot point for a fish crowder or grader.
The main drain is available in a variety of takeout angles (see picture). Choose the angle you desire and order by that part number (DD10, DD11, DD12, DD13, DD14 or DD15). The stainless steel retaining plate allows for easy attachment to liners. May also be installed in concrete or fiberglass. Made in USA.
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