Aim for these ranges as a baseline, then confirm against your specific sanitizer and test strip instructions:

• pH: 7.2 - 7.8
• Total alkalinity: 80-120 ppm
• Calcium hardness: 150-250 ppm
• Chlorine: 3-5 ppm (or bromine 3-5 ppm)

Alkalinity acts as a buffer that keeps pH stable, so it's worth adjusting first if both are off.

Test 2–3 times per week for normal household use, and daily if the tub is getting heavy use (parties, guests, multiple soaks a day). Test again any time the water looks, smells, or feels different than usual.

This is almost always a total alkalinity problem. If alkalinity is too low, pH will bounce around unpredictably (pH bounce). If alkalinity is too high, pH will creep upward over time no matter how much you adjust it. Fix alkalinity first, then re-test and adjust pH.

pH measures how acidic or basic the water is right now. Total alkalinity measures the water's ability to resist pH changes — think of it as pH's stabilizer. Low alkalinity lets pH swing wildly with every input (bathers, sanitizer, weather); correct alkalinity keeps pH steady.

Cloudy water usually comes from one of these:

• Low or depleted sanitizer levels letting organic matter build up
• A dirty or clogged filter no longer catching debris
• High calcium harness or poor pH/alkalinity balance causing mineral cloudiness
• Body oils, lotions, and cosmetic residue overwhelming the filtration

Start by testing and balancing the water, then clean or replace the filter. If cloudiness persists, shock the water and run the jets with the cover off for a few hours to help it clear.

Foam is typically caused by body oils, lotions, or detergent residue from swimsuits, or low-quality "foam-causing" chemicals built up in the water. A defoamer product will knock it down temporarily, but the real fix is a freshwater change plus rinsing swimsuits (no fabric softener) and showering before soaking.

Green tint is usually algae growth (rare in a well-sanitized hot tub but possible if it sat unused) or metals in the fill water, especially copper, oxidizing and staining the water. Brownish or rust-colored water often points to metals as well. Shock the water, run a metal sequestrant if you suspect metals, and clean or replace the filter.

A brief haze right after dosing is usually normal as chemicals dissolve and circulate — it should clear within a few hours with the jets running. If it doesn't clear, the underlying cause is more likely a dirty filter or an imbalance in calcium hardness or alkalinity.

A strong chemical smell usually means chloramines or bromamines - sanitizer that's been "used up" reacting with sweat, oils, and other organics — not too much fresh sanitizer. The fix is counterintuitive: shock the water with a higher dose to break down these compounds, rather than adding less sanitizer.

This points to organic buildup or biofilm in the plumbing lines rather than the water itself. A flush with a pipe/line cleaner product, followed by a full drain and filter cleaning, typically resolves it. Well water with naturally occurring sulfur can also cause this and may need a filtration solution at the source.

The most common culprits are pH outside the 7.2–7.8 range, chloramine buildup (see above), or sanitizer levels that are too high right after dosing. Test and balance the water, wait for sanitizer to settle to the recommended range, and shower after soaking to rinse residue.

Scale forms when calcium hardness and/or pH run too high, causing calcium to precipitate out of the water onto surfaces and equipment. Keep calcium hardness in the 150–250 ppm range and pH in the 7.2–7.8 range and consider a scale-preventing product if your fill water is naturally hard.

Rinse the filter cartridge weekly, do a deeper chemical soak/clean monthly, and replace it every 12–18 months (sooner with heavy use). A clogged filter is one of the most common causes of cloudy water and poor circulation.

Every 3–4 months for average use is the standard guideline, though heavier use or difficulty keeping chemicals balanced can mean draining sooner. A good sign it's time: you're adding more and more chemicals just to hold the same balance.

Both are effective sanitizers. Chlorine acts faster and is generally less expensive but has a stronger odor. Bromine is gentler on skin and more stable at higher temperatures but is slower-acting and typically costs a bit more. Either works well if levels are maintained consistently.

Regular sanitizer dosing maintains an ongoing baseline that kills bacteria as it forms. Shocking is a larger, occasional dose used to oxidize built-up organic waste (oils, chloramines, bacteria load) that regular dosing isn't keeping up with. Most tubs benefit from a weekly shock treatment even when the water looks fine.