Help! I'm new to sumps and I built one in my 20G long tank. I just ran a closed loop test before beginning to plumb it to my tank and it went badly. I forgot to get a picture before I emptied it and started making changes, sorry. The sketch attached was my plan for building the sump and it essentially looks like that. I also attached a photo of the sump before the test. There are 7 chambers separated by alternating baffles. the first six chambers are all 4" wide and the last chamber is 6" wide and houses the return pump, a Fluval SP4. Its hard to see in the pic but the water flows into the first chamber, then flows over the first baffle and then alternates after that going under the next baffle and so on. All baffles are 8.5 tall and the higher ones are only raised by .5". I forgot to mention, this sump design seems dumb because it is designed for my freshwater aquarium. All that's going in there are various sponges, filter pad, and biological media.
So for my test I just ran flexible plumbing from my pump back to the 1st chamber of the sump. It went very poorly. Both of the last 2 chambers were super empty and the water crashing over the baffle into the 1st emptier chamber was like a waterfall. Additionally there was not enough height difference in the alternating baffles and water was going over the baffles that it is only supposed to go under.
My two theories are that
1) the space under the baffles wasn't enough to handle the flow (its only about .5")
2) my pump is just too powerful for this small sump. I plan to adjust the pump's flow rate with a gate valve once I plumb it to the tank, but for this test at practically zero head height with no elbows or valves my pump could allegedly be pushing 1600 GPH or higher. I have a fluval SP4.
Right now I painstakingly cut out the three high baffles and plan to raise them to at least 1.25" from the bottom surface. Do people think this will work? are there other glaring issues?? Should I shrink the last 4" chamber and just make the the pump chamber bigger?
So for my test I just ran flexible plumbing from my pump back to the 1st chamber of the sump. It went very poorly. Both of the last 2 chambers were super empty and the water crashing over the baffle into the 1st emptier chamber was like a waterfall. Additionally there was not enough height difference in the alternating baffles and water was going over the baffles that it is only supposed to go under.
My two theories are that
1) the space under the baffles wasn't enough to handle the flow (its only about .5")
2) my pump is just too powerful for this small sump. I plan to adjust the pump's flow rate with a gate valve once I plumb it to the tank, but for this test at practically zero head height with no elbows or valves my pump could allegedly be pushing 1600 GPH or higher. I have a fluval SP4.
Right now I painstakingly cut out the three high baffles and plan to raise them to at least 1.25" from the bottom surface. Do people think this will work? are there other glaring issues?? Should I shrink the last 4" chamber and just make the the pump chamber bigger?
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