Sump Builder

Design your sump layout, calculate flow rates, and verify overflow safety.

Quick start — pick a recommended setup

Select a preset based on your tank size, then customize. These are proven layouts used by experienced reefers.

System dimensions

Display volume (L)Your main tank's water volume — check the manufacturer spec or use L×W×HHead height (cm)Vertical distance from display waterline down to the sump — higher = more pump power lost to gravityReturn pump (GPH)Gallons per hour at 0 head height — the number on the box. Actual flow will be lower due to plumbing friction.Return line (inches)Diameter of return pipe. 3/4 inch is standard, 1 inch reduces friction on large systems.

Sump length (cm)Sump width (cm)Sump height (cm)

Skimmer optimal level (cm)From skimmer manual

Siphon break hole

Small hole in return line above waterline

Include refugium

Chamber layout

Calculations

Effective flow

320 GPH

60% friction loss at 120cm head

Display turnover

2.7×

⚠ Low — target 3-5×

System volume

562L

Display + 112L sump

Back-siphon

2.8L

40L free space

Refugium flow

80 GPH

16.6× turnover (target 3-5×)

Refugium light

Required

40-80 μmol PAR, reverse daylight schedule

Skimmer water level

✓ OK

Operating level matches skimmer spec

Return pump turnover is only 2.7× — target 3-5× for reef. Consider a larger pump.

Refugium flow is too high (17× turnover). Chaeto will tumble violently. Target 3-5× — add a ball valve to restrict flow into the refugium section.

Adjust chamber widths and baffle heights

Drain / Filter SockWidth %Baffle cm

Skimmer SectionWidth %Baffle cm

RefugiumWidth %Baffle cm

Return PumpWidth %Baffle cm