How to Convert a Spa to Magnesium (with Sanitiser)

Magnesium and mineral salts are added in addition to a sanitiser. They enhance water feel and comfort but do not replace disinfection. More information about Magnesium & Mineral salts here.

Step 1 – Choose Your Sanitising System

• Aquaspa (Chlorine-Free)
  Sanitiser: Biguanide (no chlorine or bromine)
  Minerals: Aquaspa Sea Minerals (magnesium + potassium salts)
• Spacare
  Sanitiser: Chlorine
  Minerals: Spacare Minerals (magnesium)
• Zodiac MagnaSpa
  Sanitiser: Chlorine, brominating granules, or bromine tablets
  Minerals: MagnaSpa Minerals (magnesium blend)
• Iluka Sea Minerals
  Sanitiser: Chlorine
  Minerals: Iluka Sea Minerals (magnesium + potassium salts)

Note: Most spa equipment is perfectly fine with magnesium and mineral salts, but some manufacturers and models advise against their use (for example, certain Laing E10 circulation pumps). While we don’t necessarily agree with these restrictions, it’s important to check with your spa manufacturer or equipment supplier to ensure compatibility.

Step 2 – Add Magnesium Minerals

• Use the matching mineral product for your system (e.g., Spacare Minerals, MagnaSpa Minerals, Iluka Sea Minerals, Aquaspa Sea Minerals).
• Follow the label for dosing.
• Run pumps to circulate until fully dissolved.
• Top up minerals after topping up spa water or every few weeks as needed.

Step 3 – Balance Water Chemistry

Step 4 – Maintain Sanitiser

• Aquaspa: Maintain correct biguanide level as per label.
• Spacare: Dose as per label.
• Zodiac MagnaSpa: Dose as per label or maintain bromine at 3–5 ppm.
• Iluka: Dose as per label.
• Use a weekly oxidising (shock) treatment to help break down organics and keep water fresh.

Step 5 – Ongoing Care

• Test water 2–3× per week (pH, TA, CH, sanitiser level, minerals).
• Clean or rinse filters weekly.
• Top up minerals and sanitiser as required, especially after heavy use or water top-ups.