Here's my sump I designed and built for my 925lt Amazonian Cichlid tank build. The sump came with the tank, but I didn't like the baffle locations and chamber sizing's so I cut it all out and started fresh.
Water enters to the left at the top, tickles through some floss and Jap mat, runs left to right then down through more floss and jap mat. in the first chamber.
Then water goes up and over into 1 last layer of jap mat, 6lt of Biopure Ceramic balls and 12lt of Pond & Regular Matrix. 2x 250W Eheim Jager Heaters sit under this media with eggcrate spacing the media above the heaters. Water flows down through the ceramic media then heaters then into the next chamber, so its not heating the water then flowing over this ceramic media. (This is also part of the reason I want to be able to turn the pump up and flow more water through is so there's no "hotspots" created from the heaters, explained later on.) I live in Perth and my heaters really don't do a lot of work except for a few weeks in the middle of winter when it does get cold, so I'm not worried about overheating media in the sump having the heaters run non stop to try and keep the system to 25deg.
From there water goes up and over into K1 fluidized bed with 25lt of K1. Then lastly water flows up and through jap mat (to stop the k1 getting stuck / going through to the return chamber) and through more floss for water polishing. This baffle is also twice as thick as the others, so if I want to add some Carbon or Purigen it will go in there so the water is more likely to pass through it, rather than just sitting in the return chamber. Then into the return chamber.
I decided to go with all Ecotech equipment, which ill admit, is overkill (Vectra M2 Pump, 2x MP40QD and Battery Backup) but its my dream build so whatcha' gon' do?!.
The sump runs silent and flows really well. The system is restrained by the size of the overflow delivering water to the sump at the moment, so I'm going to make a few more changes including adding a Shadow overflow to get better flow into the sump and then I can turn the pump up. its only running at about 40% at the moment, id like to get it to around 60% to get good water turn over. Plus at the moment it only has 1 drain line to the sump, so id like to have some security built in and go to a bean animal style overflow (2 drain lines and 1 emergency). I haven't added any fish etc. yet to really test it but I did a lot of research and this designed combined all the best bits I found and wanted to try. Goodluck with your build!
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