Saltwater pools in Ohio: pros and cons

You dissolve pool-grade salt in the water, and a salt chlorine generator on the equipment pad turns some of it into chlorine as water passes through its cell. The chlorine sanitizes the pool the same way it does in any other pool, then turns back into salt, and the cycle repeats. So a saltwater pool is not a chlorine-free pool. It is a pool that makes its chlorine on site instead of from a bucket.

Pentair, whose equipment comes in our pool packages, is plain about this. Its IntelliChlor manual says the generator is designed only to produce chlorine, that it does not monitor or control chlorine levels, and that the owner is responsible for keeping free chlorine at 1 to 3 ppm in a pool. You still test the water. You just stop buying and pouring chlorine every week.

How salty is it? Pentair lists 3,600 ppm as the ideal salt level for its current IntelliChlor Plus and LT generators. NOAA puts typical sea water at about 35 grams of salt per liter, which is roughly 35,000 ppm. Pool water sits at about a tenth of that. Most people can barely taste it.

• Steady chlorine. The generator makes a little chlorine whenever the pump runs, instead of a big dose once a week that fades by Friday.
• Less chemical handling. No jugs or pucks to buy, store in the garage and carry to the pool through the season.
• The feel of the water. A lot of owners describe it as softer. That is a personal judgment, but it is the reason many people ask for salt in the first place.
• Works with automation. Pentair's IntelliChlor generators connect to its IntelliCenter and IntelliConnect controls, so you can check salt and adjust output from your phone.

Salt is an upgrade on top of our packages, which start at $68,400 installed with a Pentair variable-speed pump, a Pentair DE filter and Pentair LED lights. We price the salt system in the same quote so you see the whole number.

Fiberglass shells have a smooth, nonporous gelcoat surface, and fiberglass has a long record with salt water in boats. Salt has nowhere to soak into on the pool wall, so the shell is the least of your concerns. With salt in Northeast Ohio, the deck, the coping and anything metal nearby deserve more attention than the pool itself.

With an ICF concrete pool, the interior finish and the materials at the waterline deserve the same care we describe below for decks. Talk to us about the finish before you choose salt.

This is the Ohio-specific question, and it is worth taking seriously.

Salt water splashes onto the deck and the coping, the water evaporates, and the salt stays behind. Concrete Decor magazine, reporting on problems around salt pools, quotes an industry chemist who has seen early failure of sedimentary stone and flagstone in pool copings, waterfalls and patios, plus pop-outs in concrete, mostly in areas that go through wet and dry cycles. As the water evaporates, salt crystals form in the pores of the material. The same article notes that many of the experts it interviewed believe acrylic sealers can have real problems around salt pools.

Add an Ohio winter. Concrete that is wet and freezing, especially with salt present, is prone to scaling. The Concrete In Practice guidance published by the National Ready Mixed Concrete Association says slabs exposed to freezing and thawing with moisture or deicing salts are susceptible to scaling, and that concrete exposed to freeze-thaw cycles must be air-entrained. Pool water carries much less salt than deicer, but the principle of salt plus water plus freezing holds.

What we recommend if you want salt:

• Air-entrained concrete for the deck, placed and cured properly. That matters for any Ohio pool deck, and more with salt.
• Dense coping. Precast concrete coping or a hard, dense stone holds up better than soft, porous stone such as some sandstones and limestones.
• A breathable, penetrating sealer on concrete and pavers, reapplied on schedule.
• Rinse the deck with the hose now and then in dry spells, so salt does not keep building up on the surface.

Salt cells do not like cold water. Pentair says its IntelliChlor Plus and LT generators show a low-temperature warning when the water drops below 60 degrees and shut off at 52 degrees, plus or minus 3, to protect the cell.

That matters here. When we open pools in Northeast Ohio in May, the water is often colder than that, and it can be again in late September before closing. In those weeks the cell sits idle and you add chlorine by hand, the old way. The good news is that cold water needs very little chlorine, and Pentair makes the same point. Just do not expect the salt system to handle opening day on its own.

If you heat the pool, the cell comes back to life as the water warms. A heater and a cover make salt much easier to live with at the edges of the season.

Salt water that splashes and dries on metal is hard on it, so we talk through handrails, ladders, light fixtures and any metal furniture that will sit in the splash zone. Stainless and powder-coated hardware made for pool use, rinsed now and then, holds up far better than bare steel.

Stone around a salt pool is where people get surprised. The Concrete Decor reporting points to sedimentary stone and flagstone as the materials that failed first, in copings, waterfalls and patios that stay wet and then dry out over and over. If a natural stone waterfall or a flagstone patio is on your list, choose a dense stone and plan to seal it, or consider traditional chlorine instead. Our guide to coping options covers which materials hold up best to Ohio winters.

• Test the salt a few times a season and add bagged pool salt as rain, splash-out and backwashing dilute it. The Pentair unit reports the level too.
• Watch pH. Orenda, a pool chemistry maker, explains that the electrolysis in a salt cell releases sodium hydroxide, a very high-pH byproduct, so salt pools drift upward on pH. Expect to add acid now and then.
• Keep stabilizer up. Pentair's manual says not to let cyanuric acid drop below 30 ppm in an outdoor pool, because sunlight burns off unstabilized chlorine.
• Inspect and clean the cell. Scale builds on the plates, and Pentair notes that water hardness affects how much. If you fill from a private well, test the fill water first so you know what you are starting with.
• Plan for a replacement cell at some point. Cells wear out, and a new one is a real line in the long-term budget.

At closing, the cell drains and gets winterized with the rest of the equipment. Our pool service handles openings, closings and weekly care if you would rather not do any of this yourself.

Here is the short version we walk through with homeowners at the design stage.

Neither one is wrong. The pool sanitizes with chlorine either way. The choice is about convenience, the feel of the water, and how much attention you want to give the hardscape around it.

If you want steady chlorine without handling chemicals every week and you are building a fiberglass pool, salt is a good choice for most Northeast Ohio families. Pair it with a proper air-entrained deck, dense coping, a sealer, and a heater or cover if you want to swim in the shoulder weeks.

If you love natural sandstone or soft limestone for the patio and coping, or you know you will not keep up with sealing, think harder. Traditional chlorine is simpler on materials and costs less up front. Either way, we will show you both setups on the equipment pad during design and help you make the call.