HTH

HTH pool and spa chemicals help pool and hot tub owners sanitize water, correct its balance and handle shock treatments. The range covers routine upkeep and treatment when water conditions change. Start with a water test, then choose the treatment for the reading you get.

HTH is a pool and spa water-care brand. Its water-care history dates to 1928. Its range includes chlorine, shock, clarifier, defoamer and spa-balancing products.

Chlorine for routine sanitation

Choose chlorine tablets or granules according to your treatment routine and equipment. Application directions matter because the chemical has to reach the water the intended way. If you’re using a feeder, match the chemical to the feeder’s compatibility instructions and follow the chlorine product’s label.

Shock for pool maintenance and algae treatment

HTH offers calcium-hypochlorite shock and recommends shocking at least once a week during swim season. That gives you a maintenance schedule to work from. Test before adding shock: HTH specifies pH of 7.2–7.6 and says high pH reduces shock effectiveness.

For green water, determine your pool’s gallonage and use the algae-treatment directions on the exact shock product. A bag count only helps when it matches the pool volume and treatment. Follow the label for the dose and spacing between chemicals.

Keep shock out of the skimmer, floater and feeder, as HTH directs. Give each chemical its own application according to its label, and keep different pool chemicals separate.

Returning to the water

A fresh water test is the deciding check before swimming. HTH requires testing with its 6-Way Test Strips before pool re-entry, with free available chlorine back at 1–4 ppm. Plan swimming around that measured result.

For spa re-entry, HTH specifies free available chlorine of 3–5 ppm. Keep bathers out while adding spa chemicals, then test for that range before soaking.

Spa chlorine and water balance

Match the sanitizer to your spa system: HTH spa Clear Chlorinating Sanitizer is intended for chlorine systems. Use the product label for dosing, safety and storage.

HTH also offers spa balancers. Choose a pH adjustment from your water-test result; a decreaser is for a high reading. Base the dose on the spa product’s label and your spa’s water volume.

Water-care specifications

Chlorine readings below are free available chlorine, measured in parts per million. Use the pool or spa range that applies to your water.

Measurement or fit	HTH specification
Pool pH in shock guidance	7.2–7.6
Pool total alkalinity in shock guidance	80–120 ppm
Pool chlorine before re-entry	1–4 ppm
Spa chlorine before re-entry	3–5 ppm
HTH spa Clear Chlorinating Sanitizer system fit	Chlorine systems

Frequently Asked Questions

How long after using HTH shock can you swim?

HTH shock guidance calls for at least eight hours of continuous filtration, but elapsed time alone doesn’t tell you when you can swim. Before getting back in, test with the recommended strips and confirm that free available chlorine is back at 1–4 ppm. If it’s still above that range, you’ll need to wait and test again.

Is HTH pool shock good?

HTH pool shock is a practical choice for routine maintenance and algae treatment when you match the dose to your pool volume and water condition. High pH reduces shock effectiveness, so your water-test results matter as much as the treatment. Evening is the recommended application time, with the pump running.

How do you use the HTH 6-Way Test Kit?

With the HTH pool test kit, you compare a treated pool-water sample against a color-coded chart to read the results. Follow the kit’s instructions for sample amounts, testing steps and when to read each result. The dipping and waiting instructions for test strips aren’t the procedure for this kit.

What kind of chlorine tablets does HTH make?

HTH Brilliance Cal Hypo Chlorine Tablets are calcium-hypochlorite tablets for pool sanitation. Your feeder has to be compatible with that chemical, so check its instructions as well as the tablet label. Tablet shape alone doesn’t establish compatibility.