look on ebay for a "prefilter box" I think is how they are listed
there are 300, 600, 900 and 1200 gph
models - I'd go with the 1200 gph
for a 75 gallon tank
I think they're in the $50-60
for a pump I'd go with a dolphin DP-1200 ... dolphin are VERY quiet and can be plumbed externally or internally.
for a sump, I'd go with a 20 or 30 gallon tank, 'long' rather than 'high'
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