Different things in the sump mandate different flow rates. For example, UVs require low flow (eg 100-200 GPH) for ich and high flow (eg 700-800 GPH) for bacteria/algae. My new Pax Bellum says it wants 200-400 GPH. Biomedia works well at high flow rates, but too high and it breaks apart. Now toss in a couple reactors for biopellets/carbon/GFO/etc and suddenly you need about 5 different flow rates through various components. The easy solution is closed loops in your sump. However, since the goal is to process X GPH of display water, suddenly it becomes a lot trickier to figure out how much of the display is passing through each component.
The BRS video on UVs said it's a mistake to use a closed loop in your sump and suggested attaching it to your display (which may be difficult or undesirable depending on plumbing and room layout) or return pump (which gets you 1 fairly medium-high flow rate, or possibly 2 if you're running dual return pumps at different speeds -- can you even do that?). So...
1. Should closed loops in the sump be avoided?
2. Is there a way to calculate the effective display tank turnover when using a closed loop in the sump?
3. Can you have 2 return pumps with different speeds?
4. Why are apex flow monitors so incredibly overpriced and require a special extra box instead of plugging directly into the unit?
The BRS video on UVs said it's a mistake to use a closed loop in your sump and suggested attaching it to your display (which may be difficult or undesirable depending on plumbing and room layout) or return pump (which gets you 1 fairly medium-high flow rate, or possibly 2 if you're running dual return pumps at different speeds -- can you even do that?). So...
1. Should closed loops in the sump be avoided?
2. Is there a way to calculate the effective display tank turnover when using a closed loop in the sump?
3. Can you have 2 return pumps with different speeds?
4. Why are apex flow monitors so incredibly overpriced and require a special extra box instead of plugging directly into the unit?
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