Sizing, placement, and maintenance guidance for surface-water irrigation intakes—plus a practical comparison table and FAQ schema.
Author: Green Guru LLC•Published on •Last edited on
Quick answer:40G fits pumps under ~40 GPM in moderate debris. 80G fits higher flows, heavy algae/organics, or longer intervals between clean-outs. Near the 40 GPM limit, sizing up is typically safer for surface water.
What BIGFOOT® is (and why it matters)
BIGFOOT® is a suction-side intake filter family built for surface-water irrigation pumps drawing from lakes, ponds, rivers, or retention basins. It reduces intake velocity by spreading suction across a wide screen area—helping reduce clogging while protecting the pump.
BIGFOOT® models: 40G vs 80G
40G: commonly listed with a 6" outside screen and 2" inside screen, with a 2" suction connection.
80G: commonly listed with a 12" outside screen and 6" inside screen, with a 2" suction connection and larger intake area.
Model comparison
Model
Best for
Typical notes (verify)
BIGFOOT® 40G
Pumps <~40 GPM, moderate debris
Smaller screen footprint; more frequent clean-outs during algae spikes
BIGFOOT® 80G
Higher flows, heavy organics, longer intervals
More screen area; typically safer choice near the 40 GPM line
Dual 40G (Series)
Shallow-water or algae-heavy intakes
Two 40G assemblies inline; sealing and restriction management are critical
Availability
Service includes confirming fit, sizing, and the full intake assembly. When a BIGFOOT®-style intake is already installed, service can verify configuration, sealing, and maintenance approach to reduce prime loss and mid-season surprises.
Field note: dual BIGFOOT® 40G inline (series) — fully submerged
We have successfully run two BIGFOOT® 40G filter assemblies inline (in series) as a fully submerged intake (mostly horizontal; one deployment vertical on a steel seawall on Lake Erie), using synthetic filter media matting.
Typical sequence (as built):
Drawline (1½", 2", or 2½") → male adapter → PVC check valve → 2" × 6" PVC threaded nipple → BIGFOOT® 40G Filter A → 2" × 6" nipple coupling → BIGFOOT® 40G Filter B.
Optional: brass 2" foot valve installed inside Filter A on some builds (verify compatibility and serviceability).
Critical cautions
Air leaks kill suction: every threaded suction-side joint must seal perfectly.
Restriction compounds: two filters in series can reduce flow as media loads—monitor and clean.
Valve stacking: avoid check/foot valve conflicts and keep servicing practical.
Placement and maintenance
Keep the intake off the bottom to avoid silt loading.
Inspect after early runs; algae season can load screens rapidly.
Clean screens/media as needed—bigger intake area generally means longer intervals.