Domakihub Hot Tub Maintenance Basics: Keep Your Spa Clean and Safe
A practical routine to protect your hot tub, your guests, and your water quality year-round.
Reviewed by Domakihub pool pros · 2026-06-23 · 5 min read
A hot tub is one of the most appealing amenities you can offer at a Greek villa, holiday rental, or boutique hotel — but without a consistent maintenance routine, the water can turn cloudy, foamy, or even unsafe in just a few days. The video above walks through the core chemical and mechanical steps; this guide gives you the ordered routine to follow from the very first fill. Whether you manage a seasonal property in Crete or a year-round residence in Athens, the same five-step rhythm keeps your spa inviting and compliant with health standards.
Why Hot Tub Water Goes Wrong So Fast
Hot tubs hold far less water than a swimming pool — typically 1,000 to 2,000 litres — yet they operate at 37–40 °C and host multiple bathers in a compact space. This combination accelerates the consumption of sanitiser, drives up pH, and creates ideal conditions for bacteria such as Pseudomonas and Legionella if the water is left untreated. In the Greek summer, ambient heat puts extra pressure on temperature control and evaporation rates.
The good news is that correcting imbalances is quick when you catch them early. A twice-weekly test-and-adjust habit is nearly always enough to stay ahead of problems, especially when you pair it with a weekly filter rinse and a quarterly full drain.
What Chemicals You Actually Need
You do not need a large collection of products. Three categories cover almost every situation: a sanitiser (chlorine granules or bromine tablets, your choice), a pH adjustment pair (pH Plus and pH Minus), and an alkalinity increaser. Optionally, a non-chlorine shock oxidiser clears organic waste after heavy use without forcing bathers to wait the usual 24 hours that chlorine shock requires.
In Greece, tap water tends to arrive with moderate-to-high alkalinity and calcium hardness, especially in island areas where the supply comes from desalination or limestone-rich aquifers. Test your fill water before adding any chemicals so you know your starting baseline and avoid overcorrecting on the first day.
The 5-Step Hot Tub Maintenance Routine
- 1
Test and balance the water
Use a test strip or liquid test kit to check three values in order: total alkalinity (target 80–120 mg/L), pH (target 7.4–7.6), and then sanitiser level (free chlorine 3–5 mg/L or bromine 3–6 mg/L). Always adjust alkalinity first, because it buffers pH. Add chemicals one at a time with the jets running, wait 15 minutes, then re-test before adding the next product. Do this at least twice a week during active use.
- 2
Add sanitiser and shock after each heavy use
After a group session or whenever the water looks dull, dose with sanitiser to bring levels back to the target range and follow with a non-chlorine shock oxidiser. Shock burns off the chloramines and organic compounds that cause that sharp chemical smell and irritate skin. Run the jets for 20 minutes with the cover off to allow off-gassing, then replace the cover. Aim to shock at least once a week regardless of use.
- 3
Rinse the filter every week
Remove the filter cartridge, rinse it thoroughly with a garden hose to dislodge debris between the pleats, and reinstall it. A clogged filter reduces circulation and forces the pump to work harder, which shortens equipment life and lets contaminants build up. Every two to three months, deep-clean the cartridge by soaking it overnight in a dedicated cartridge cleaner solution, then rinsing again before reinstalling. Replace the cartridge entirely at least once a year.
- 4
Wipe the waterline and check the cover
A ring of body oils, sunscreen, and mineral deposits forms at the waterline within days. Wipe it away with a soft cloth and a non-abrasive spa surface cleaner each week to prevent staining and bacterial film. While you are at it, inspect the cover: it should be firm, dry on the underside, and free of cracks. A saturated or cracked cover loses insulation, drives up electricity costs, and lets debris into the water — a particular concern at open-air properties near olive groves or the sea.
- 5
Drain, clean, and refill every three to four months
No amount of chemical adjustment restores water once total dissolved solids (TDS) become too high. Every 90–120 days, fully drain the spa, scrub the shell with a gentle spa surface cleaner, rinse clean, and refill with fresh water. Before you refill, inspect the jets, pillows, and fittings for limescale or biofilm. This is also the right moment to flush the plumbing with a line-flush product, which dislodges the biofilm that hides inside the pipework where no chemical dose can reach it.
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FAQ
- How often should I change the water in my hot tub?
- Every three to four months for a regularly used tub, or sooner if the water becomes stubbornly cloudy or foamy despite correct chemical levels — a sign that total dissolved solids are too high to manage with dosing alone. Holiday rentals with back-to-back bookings may need a full drain and refill every two months during peak season.
- Is bromine better than chlorine for a hot tub in Greece?
- Both work well, but bromine has a slight edge in hot water because it stays active at higher temperatures and produces less of the harsh smell associated with chloramines. Chlorine is easier to source across most of Greece and is perfectly effective if tested regularly. The choice often comes down to personal preference and what your local pool supply shop reliably stocks.
- What causes foamy water and how do I fix it?
- Foam is almost always caused by body lotions, shampoo, sunscreen, or detergent residue from swimwear. Rinse swimwear in plain water before entering the spa and ask guests to shower first. For an active foam problem, add a dose of liquid spa defoamer for immediate relief, then shock the water and check your sanitiser and pH levels. If the foam persists for more than a day or two, a full drain and refill is the quickest and most reliable fix.