Hot Tub Troubleshooting: Cloudy Water, Low Chlorine & When to Call Us

Most hot-tub "problems" are really just water chemistry drifting a little, and almost all of them have a simple fix. Here are the ones we get asked about most, what's usually behind them, and where the line is between a five-minute fix and a "bring us a sample" moment. The golden rule underneath all of it: when in doubt, take things out of the water (drain, filter, balance) before you put more things in.

Cloudy or dull water

Usually one of three things: the water's out of balance, the filter needs a clean, or organic gunk (lotions, oils) has built up faster than the sanitizer can oxidize it.

• Test and balance first. Get pH and alkalinity back in range (pH 7.2–7.8).
• Clean the filter. A clogged filter can't clear water, no matter how good the chemistry is.
• Shock it. A dose of quick-dissolving chlorine oxidizes the non-filterable waste that's clouding things up. Still hazy after balancing, filtering, and shocking? That's a good time to just do a fresh fill.

Low or no chlorine — even at a high setting ("chlorine lock")

This is the classic head-scratcher: the water looks clear, but day after day you read little or no chlorine, even with the output cranked up. The usual culprit is cyanuric-acid (CYA) build-up, the stabilizer in dry granular "dichlor" chlorine. Overuse it and the CYA binds your free chlorine and kills its punch. (Carry-over from pool water can do it too.)

• The fix is to take it out, not add more: drain and refill.
• Prevent it by letting the salt system do its job. Use Boost (or raise the output level) to recover after heavy use, instead of dumping in chlorine. If you must add chlorine, use unstabilized liquid chlorine or bleach (no CYA), never scented or "splash-free" bleach — and know it nudges pH up, so re-balance afterward.

Scale, crusty buildup, or a short-lived salt cartridge

That's hard water — too much calcium. High calcium scales the salt cartridge and shortens its life, stresses the heater, and clouds the water. Keep calcium hardness in the 25–75 ppm range.

• Mild (75–150 ppm): a FreshWater Vanishing Act® pillow. It comes in the startup kit.
• Higher (150–300 ppm): a larger Vanishing Act XL™ or a portable softener.
• Very hard (over 300 ppm): fill through a portable or household softener from the start. Much easier than fixing it after. On well or known-hard supply, this is worth doing every fill.

Foamy water

Usually body oils, lotions, and detergent residue plus older water. A filter clean clears it up — and if it persists, a fresh fill will. Rinsing off before a soak helps prevent it.

Metal stains (well water)

Iron or manganese in fill water can stain. They should be below 0.5 ppm (copper below 0.2 ppm) before start-up. A garden-hose pre-filter on fill catches most of it, which matters most on well supply.

Error codes and equipment

Your spa's panel may flash a code for things like flow, temperature, or a sensor. We're deliberately not listing codes here, because they differ by model and year, and the last thing you want is a guide telling you the wrong thing about your equipment. Your model's manual has the exact code list. If a code involves the heater or pump, or won't clear after a filter clean and restart, that's a call, not a DIY.

When to call us

Fix it yourself: cloudy water, balance drift, chlorine lock, scale, foam. Call us for: a persistent error code, no heat, a pump that won't prime or is noisy, a leak, or any chemistry you've balanced twice and still can't hold. There's no prize for guessing on equipment. That's what your local team is for.