Originally Posted by Ocho Cinco
I guess I don't know what that means or how to use that info towards making this set up.
Basically you'll need to calculate the volume of water that will drain out of the display and frag tub when the return pump is turned off. Then make sure that the sump will accommodate the extra water. Here are the equations to use: Display overflow volume
= (length x width x height*) / 231 Frag tub overflow volume
= ((length of the straight edge x width between the two straight edges) + ((.5 x width between the two straight edges) x (.5 x width between the two straight edges) x 3.14) x height*) / 231
*height = distance from waterline (when system is running normally) down to the bottom of the overflow weirs. Sump capacity volume**
= (length x width x waterless height (distance from the waterline to the top of the tank)) / 231
** may need to do this calculation several times if the sump has sections with different water heights. If that is the case use the sections length and width rather than the whole tanks and add the volumes together.
All lengths should be measured in inches and all volumes will be in gallons.
Add the display and frag volumes and design the sump so that it can handle about 10% more water.