DIY plumbing

Aquarium Plumbing Parts Guide: Bulkheads, Unions, Valves

Proper plumbing makes the difference between a tank you maintain in 30 minutes a week vs one that floods your floor when a pump fails. This guide covers every part you need, why each matters, and where to use it.

Time4 hours

Cost$80-300

DifficultyIntermediate

Bulkheads

A bulkhead is a threaded fitting that passes through a drilled tank hole. It seals with a rubber gasket on the wet side. Sizing: 1" bulkhead handles ~600 gph drain capacity; 1.5" handles ~1,200 gph; 2" handles ~2,400 gph. Always oversize for safety. Brands: Lifegard Aquatics (most common), Hydor, BRS.

Critical detail: the rubber gasket goes on the WET side (inside the tank). Backwards = leaks. Hand-tighten only - over-torquing cracks the glass.

True unions vs couplings

True unions are screw-together joints that let you disconnect plumbing without cutting. Always use them around: pumps, reactors, UV sterilizers, anywhere you might need to remove the component for cleaning. Cost: $5-15 each.

Couplings (slip-only) are permanent. Use them for non-serviceable runs only.

Ball valves vs gate valves

Ball valves ($5-15): full open or full closed. Quick. Used as shut-offs. Gate valves ($25-50): infinite adjustment. Used for fine-tuning flow on returns + drain lines. The Herbie + Bean Animal silent overflow methods require gate valves.

Schedule 40 vs Schedule 80 PVC

Schedule 40 white PVC: standard, $1-3 per ft. Adequate for any home aquarium. Schedule 80 grey PVC: thicker walls, $3-6 per ft. Used by pros for visual aesthetics and slightly higher pressure. Both work. Don't mix sizes - 1" Sch 40 ID is different from 1" Sch 80 ID.

Slip vs threaded

Slip fittings need PVC primer + cement. Permanent + leak-proof. Threaded fittings use Teflon tape. Removable but more leak-prone. Use slip for permanent runs, threaded only at component interfaces (pump intake/outlet).

Standard parts list for a sump build

(2) 1" bulkheads (overflow + return)
(2) 1" true unions
(2) 1" ball valves (return shut-off + drain shut-off)
(1) 1" gate valve (Herbie drain fine-tune)
(2) 90° elbows
(2) tees (for emergency drain redundancy)
10 ft of 1" Schedule 40 PVC
(1) bottle PVC primer + (1) bottle PVC cement
Teflon tape

Total cost: ~$80-150 from Home Depot or BRS.

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