Regulators

What to look for in a scuba regulator

Frequently asked questions

What is included in a complete scuba regulator set?

A complete regulator set includes a first stage (attaches to the tank valve), a primary second stage (the one you breathe from), and a backup second stage — commonly called an octopus — for sharing air with another diver in an emergency. A regulator package adds to this a gauge console or dive computer, hoses, and sometimes a regulator bag. Individual first and second stage sets can be purchased separately if you already have a backup regulator or plan to select one independently.

What is the difference between a piston and diaphragm first stage?

A piston first stage uses a metal piston and spring to regulate the pressure between your tank and the intermediate pressure system — simple, durable, and common in recreational regulators. A diaphragm first stage uses a rubber diaphragm to perform the same function, which isolates the internal mechanism from the surrounding water. This makes diaphragm designs better suited to cold, silty, or contaminated water environments because the internal parts are less exposed to the water conditions. Most environmentally sealed regulators designed for cold water and technical diving use a diaphragm or sealed piston design.

Can I use the same regulator for both warm and cold water diving?

Yes — most mid-range and high-end regulators in our range perform well in both environments. The key variable is whether your first stage is environmentally sealed. The Scubapro MK17 EVO2, MK19 EVO, and MK25 EVO are all sealed designs that handle cold Canadian water and warm tropical water equally well. The Cressi MC9 and Scubapro MK11 are better suited to warm water only — they are lighter, more compact, and excellent travel regulators, but not the right choice for cold-water diving in Canada. When in doubt, call us at (888) 483-0049 and describe where you dive most often.

How often should my scuba regulator be serviced and what does it involve?

Most manufacturers recommend a full service every one to two years or every 100 dives, whichever comes first. A service involves disassembling the first and second stages, replacing internal o-rings, seats, and springs, cleaning all components, reassembling, and testing breathing performance against factory specifications. Regulators used in cold or silty water benefit from more frequent servicing. A regulator that has not been serviced on schedule may breathe harder, develop a free-flow, or fail unexpectedly — in a life-support device, deferred maintenance is a safety issue, not a preference. Servicing regulators requires specialized tools and equipment as well as brand-specific training. Our technicians are highly trained and have many years of experience servicing scuba regulators.