The technical spec you'll see most often when choosing pool equipment is "AISI 304/316 stainless steel." The difference between the two alloys rarely gets explained well — yet the wrong choice, especially on salt-water or coastal projects, can lead to corrosion and voided warranties within a few years.
The key chemical difference: molybdenum
AISI 304, with roughly 18% chromium and 8% nickel, is the most widely used austenitic stainless steel in the pool and food industries. AISI 316 has the same chromium-nickel ratio plus 2-3% molybdenum. That small addition meaningfully increases the steel's resistance to chloride ions — salt, sea air, heavy chlorination.
In practice: AISI 304 performs well in standard mains-water, chlorine-disinfected indoor pools. AISI 316 is the better call for salt-chlorinated pools, outdoor facilities near the coast, and semi-Olympic or Olympic pools with heavy chemical use.
Which grade belongs on which equipment?
For parts that stay in constant contact with water and are hard to remove — ladders, skimmer housings, main drain grilles, LED fixture bodies — specifying AISI 316 in salt-water systems saves on labour and replacement cost over the equipment's lifetime. For more accessible parts running in chlorinated fresh water, such as waterfall spouts and decorative water features, AISI 304 is sufficient and more economical.
SNY Pool manufactures in both grades according to the project specification; the material used for each product is listed under the "Material" field on its product page.
Maintenance habits that slow corrosion
Even the best stainless steel can develop pitting corrosion if left unmaintained. Regularly checking water chemistry (pH 7.2-7.6, free chlorine 1-3 ppm), avoiding over-chlorination, and wiping metal surfaces a few times a year with a neutral-pH stainless cleaner will significantly extend equipment life.
Direct contact between dissimilar metals — for example, galvanized steel fasteners against a stainless body — can cause galvanic corrosion, so using compatible fixings during installation matters too.
Browse Stainless Steel Equipment
Vitality Pool systems, pre-filters, weir grilles, wall massage nozzles, floor air systems, showers and shower tunnels.
