How Often Should You Drain and Refill a Las Vegas Pool?

Quick Answer: Most pools in a hard-water desert need a full drain and refill roughly every three to five years. Over time, dissolved minerals and other solids — measured as total dissolved solids, or TDS — keep concentrating because water evaporates and you refill with more hard water, until no amount of chemistry keeps the water balanced. Signs it's due include stubborn cloudy water, chemicals that stop working, persistent scale, and high TDS or calcium hardness readings. A drain-and-refill is also the ideal time to clean the now-exposed tile and, if needed, acid wash the plaster.

There's a point where your pool water just stops cooperating — you add chemicals, the levels barely move, the water looks tired, and scale keeps forming no matter what you do. That's usually not a dosing problem. It's the water itself telling you it's time for a fresh start, and in the desert, that comes around more often than most pool owners expect.

Why Desert Pools Need Refreshing at All

Every time pool water evaporates, the minerals and dissolved solids it carried stay behind. You top the pool off with more hard water, which adds even more, and over months and years, the total dissolved solids — TDS — climb steadily. TDS is everything dissolved in the water: calcium, salts, and the leftover byproducts of years of pool chemicals.

Once TDS gets high enough, the water becomes saturated, and chemistry stops behaving. Chlorine works less effectively, balancing becomes a losing fight, scale forms more readily, and the water can look dull or cloudy even when your test numbers look close. At that point, no amount of adjusting fixes it, because the problem is the sheer concentration of stuff in the water. The only real solution is to replace a large share of the water with fresh.

The Typical Timeline Here

In hard water desert conditions, the common interval is every three to five years — sooner than in milder, softer-water regions, because the high source-water hardness and fast evaporation push TDS up faster. It's a range, not a fixed date, because your exact pace depends on a few things.

Factor	Pushes drain interval sooner	Pushes it later
Source water hardness	Very hard water	Softer water
Evaporation/heat	Heavy summer use, features running	Cooler, covered, less use
Top-off frequency	Frequent refills with hard water	Steady levels, less refilling
Pool chemistry history	Heavy chemical use over years	Light, well-managed dosing
Bather load	Busy, high-use pool	Lightly used pool

Rather than going strictly by the calendar, the better approach is to watch the water and test it. TDS and calcium hardness readings objectively indicate when the water has reached the end of its useful life.

Signs It's Time for a Drain and Refill

A few signals tend to show up together when a pool is due. The water turns persistently cloudy or dull and won't clear up with normal treatment. Chemicals seem to "stop working" — you add chlorine or balancer and see little effect. Scale and calcium keep forming quickly even after cleaning. And your test readings for TDS or calcium hardness come back high, above the range your water can carry. When several of these line up, the water has aged out.

Test your TDS and calcium hardness once or twice a year and write the numbers down. A steady climb toward the high end is your early warning that a drain-and-refill is coming, so you can plan it for the right season instead of reacting to green water in July.

Make the Most of an Empty Pool

A drain-and-refill is more than a water swap — it's the one time the pool is empty and surfaces normally underwater are exposed and accessible. That makes it the ideal moment to clean the tile thoroughly, since the calcium band and any buildup below the normal waterline can be reached and removed all at once. If the plaster interior is stained or dull, it's also the natural time to consider an acid wash while the surface is bare. Pairing these jobs with the refill means you get fresh water and a freshly cleaned pool in one coordinated effort instead of scheduling them separately.

A word of caution on the draining itself: emptying a pool isn't risk-free, since an empty shell can be affected by ground conditions, and a plaster surface left exposed to the sun can be damaged if it sits too long. It's best done deliberately and at the right time of year, not on a whim during peak heat.

Plan the Refill Around the Right Season

Because a drained pool is vulnerable while it's empty, timing the job well matters as much as doing it at the right interval. The milder shoulder seasons — spring and fall — are generally the friendlier windows, since the plaster isn't baking under peak summer sun and the new fill water isn't immediately fighting maximum evaporation. Scheduling the drain for cooler weather also makes any tile cleaning or plaster work more comfortable to complete without racing the clock.

It helps to line up the work before you pull the plug. Knowing in advance whether you'll just refresh the water, clean the tile, or also acid wash the plaster lets everything happen in one efficient empty-pool window rather than draining, discovering more to do, and leaving the shell exposed longer than it should be. A little planning turns a refill from a stressful scramble into a routine, well-sequenced reset.

The Payoff of Staying on Schedule

Keeping to a sensible drain-and-refill rhythm does more than clear cloudy water. Fresh water with manageable TDS means your chemicals work properly again, so you spend less on dosing that wasn't accomplishing much and less time chasing a balance that wouldn't hold. Scale forms more slowly in water that isn't already saturated with minerals, which eases the load on your tile and equipment alike. And pairing the refill with a thorough tile cleaning means you reset both the water and the surfaces at once — the pool looks and behaves like new, rather than limping along on tired, over-concentrated water until the next green-water emergency forces your hand.

Frequently Asked Questions

How do I know my pool's TDS is too high?

Test it. Total dissolved solids are measured with a meter or test kit, and when the reading climbs well above the recommended range, the water is saturated and chemistry struggles. The practical signs back this up: chemicals stop working, water looks dull, and scale forms fast. High TDS combined with those symptoms is the clearest sign a refill is due.

Can't I just keep adjusting chemicals instead of draining?

Up to a point. Balancing works until TDS gets too high, and then adding more chemicals barely moves the numbers and can even make things worse by adding to the dissolved load. Once the water is saturated, replacing a large share of it with fresh water is the only thing that actually resets the chemistry. Endless dosing is a losing battle at that stage.

Is it bad to drain a pool in the desert summer?

It carries more risk in peak heat. A bare plaster surface exposed to intense sun can be damaged if it's left empty too long, and the job is harder to manage when it's extremely hot. Many owners schedule a drain-and-refill for milder parts of the year and have it done efficiently so the pool isn't sitting empty in the worst conditions.

Should I clean the tile while the pool is drained?

It's the ideal time. With the water out, the full waterline and the area just below it are exposed and reachable, so calcium and buildup can be removed all at once rather than working around the water level. Many people coordinate a tile cleaning — and an acid wash of the plaster if it's stained — with the refill to handle everything together.

Does a fresh refill prevent calcium from returning?

It lowers the dissolved mineral concentration, which helps, but the refill water is still hard, so calcium will gradually build up again. A drain-and-refill resets the water, not the source. It's an important part of desert pool care, but it works best paired with balanced chemistry and periodic tile cleaning to manage the calcium that returns.

Watch the Water, Not Just the Calendar

Desert pools generally need a drain and refill every three to five years because hard water and heavy evaporation push total dissolved solids up until chemistry stops working. The exact timing depends on your water, your heat, and your habits, so test your TDS and calcium hardness and let the numbers guide you. And when you do refill, take advantage of the empty pool to clean the exposed tile and refresh the plaster — fresh water and a clean pool in one coordinated job.

Draining your pool and want the tile spotless before it refills? — Get the exposed waterline cleaned with gentle media blasting while the pool is empty. Pool Tile Cleaning Vegas serves Las Vegas, Henderson, North Las Vegas. Call (702) 743-8142.