Hi,
I recently made on for my 75g ( I believe the 55 is the same foot print )
I had similar research "issues"
anyway. I used a 30g sump tank
12" wide
30" long
18" deep
I cut 4 pieces of plexiglass 12" Height by width of tank ( 12" )
3 were for the bubble trap- spaced 1" appart
- 1st piece sits on bottom of tank ( water flows over )
- 2nd piece is 1.5" off bottom of tank ( water flows under )
- 3rd piece sits on bottom of tank ( water flows over )
1 seperates the return section from the "future-something" section. sits on bottom of tank ( water flows over )
my dimensions are: ( Left to right )
Drain/skimmer- 10" wide by 12" Height ( 6.2 Gallons )
Return- 11" wide by 12" Height ( 6.8 Gallons )
Future- 6" wide by 12" Height ( 3.7 Gallons )
being that I am only using the first 12" of tank height, that leaves me with 6" of tank height to spare ( 18" high - 12" used )
6" of height in my sump is room for over 9 Gallons of water... this is important because you need room for when the power goes out and some water drains from the Display Tank above. for me... my tank DT is 48" Length by 18" wide. So for every one inch of water dropping from the DT, I will need 3.74gallons of space in the sump.
my 75g only drops about 1 inch if power goes out, and if the entire corner flow section drains that would be another 3 gallons.. so my emergency space is plenty
3.74 gallons- power out effect from DT
3 gallons if corner flow fully drains ( has not happened yet )
Total 6.74.... is less than my 9 Gallons of space in the sump, yippee
Let me know if you need any other measurements. Bubble trap works awesome, but it is tricky getting that darn thing siliconed in there. I used long popsicle sticks.
btw, I am using the Mag 9.5 and it is only dialed down a little bit. 7 would be too little for my application I think.
Good Luck!!!
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