1/2" & 3/4" BSP Male Bulkhead Connector – ABS Pipe Fittings for Aquarium & Fish Tank

Measure the hole diameter in your tank wall or sump panel. A 1/2" BSP male bulkhead typically requires a drilled hole of approximately 1" (25mm), while a 3/4" BSP fitting generally needs around 1-1/4" (32mm). Always verify against your specific tank material and wall thickness before drilling. When in doubt, size up — a slightly larger hole is easier to seal than one that's too small.

ABS fittings are generally rated for low-to-medium pressure applications. For aquarium and fish tank use, they are typically sufficient for gravity-fed drain lines and low-pressure return pump systems. For high-pressure plumbing applications, a different material such as Schedule 40 PVC or brass is generally recommended. Contact us to confirm pressure ratings for your specific use case.

ABS plastic is generally resistant to freshwater and is widely used in freshwater aquarium plumbing. For saltwater (marine) setups, ABS can typically be used in low-salinity or short-term applications, but PVC or CPVC fittings are generally preferred for long-term saltwater exposure due to better chemical resistance. Contact us to confirm suitability for your specific marine setup.

These fittings use BSP (British Standard Pipe) threads, which are not directly interchangeable with NPT (National Pipe Thread) fittings commonly found in US residential plumbing. BSP and NPT have different thread angles and pitches. Please confirm your existing fittings and valves use BSP threads before ordering to avoid compatibility issues.

A basic sump system typically requires at least 2 bulkhead fittings — one for the gravity drain line and one for the return pump line. More complex setups with dual overflows, emergency drain lines, or multiple return outlets may need 4 or more. We offer packs of 1, 2, 5, and 10 pieces so you can order exactly what your build requires without overpaying for excess stock.

ABS plastic is generally suitable for outdoor use in moderate climates and is commonly used in pond filtration plumbing. However, prolonged direct UV exposure can cause ABS to become brittle over time. For outdoor pond applications, in most cases it is advisable to protect fittings from direct sunlight or to use UV-stabilized PVC alternatives for permanent long-term installations.

Installation typically requires: a hole saw or step drill bit sized to the required panel hole diameter, a wrench or adjustable pliers for tightening the locknut, and PTFE (Teflon) tape applied to the male threads for a watertight seal. No soldering, threading machines, or specialized plumbing tools are generally required for standard aquarium tank wall installations.