Algaecide — 1 L

Goes in to stop algae taking hold while the pool sits unattended. At closing this is the chemical doing the most work over the winter; at opening it clears the way before the filter has caught up.

Stain and scale control — 1 L

Holds dissolved metals and calcium in solution so they do not deposit on the liner, the tile line or the steps while the water is still and cold.

Oxy Clear Shock — 2 × 454 g

An oxygen-based (non-chlorine) shock that burns off organic waste. Two pouches: the usual pattern is one at the start of the job and one held back, but follow the pouch.

• Covers the three jobs a pool needs at either end of the season — algae control, stain and scale control, and a non-chlorine oxidiser — in one box
• Sized for pools up to 80,000 L, which covers most residential inground pools
• The shock is oxygen-based rather than chlorine-based, so it will not spike free chlorine or bleach a fresh winter cover
• Works as an opening kit in spring and a closing kit in fall — the same three chemicals do both jobs
• Each component is a full-size retail bottle or pouch, not a sample sachet

Using it at opening

Balance the water first. Chemicals added to unbalanced water are largely wasted, and stain and scale control in particular depends on pH being in range to do anything at all. Run the filter continuously through the first 24 to 48 hours.

Using it at closing

These go in as the last step, after the water has been balanced and lowered and before the cover goes on, so the chemicals are distributed through the whole body of water rather than sitting on top of it. Run the pump long enough to circulate them fully before shutting down.

Dosage, safety and storage

• Each of the three products carries its own label, dose rate and Safety Data Sheet. Dose from the bottle in front of you, not from a kit-level instruction — the rates differ by product and by pool volume.
• Never mix these products together, and never combine them in the skimmer. Add one at a time, with the pump running, and let each circulate before the next goes in.
• Store the box closed, cool, dry and well ventilated, out of reach of children, away from heat, open flame, and other pool chemicals.
• If you are not sure what your water needs, bring a sample in. A free water test takes a few minutes and will tell you whether this kit is the right starting point for your pool.