Green Hot Tub Water - Why It Happens and How To Clear

Green Hot Tub Water - Why It Happens and How To Clear

Is your hot tub water turning an unsightly shade of green? Not only is it unappealing, but it also indicates a potential chemical imbalance, making your hot tub unsafe for use. In this post, we'll delve into the reasons behind green hot tub water, the culprits causing it, and how to restore crystal-clear water while preventing future green water woes.

What Causes Hot Tub Water to Turn Green?

  1. Lack of Sanitizer in the Water / Algae Growth:

    • In most cases, insufficient sanitizer levels (like chlorine or bromine) are the main culprit. This allows algae to thrive and grow in the water. Neglecting water maintenance over an extended period, heavy hot tub usage leading to rapid sanitizer depletion, or factors affecting sanitizer efficiency can contribute to this issue.
  2. Excessive Metals:

    • Even if sanitizer levels are within the recommended 3-5ppm range, your water might still exhibit a greenish tint due to excessive metals present. These metals can originate from the source water or spa components, reacting with the water and causing the greenish hue.

How to Clear Green Water from Your Hot Tub:

  1. Shock the Water and Clean Filters:

    • To eliminate potential algae growth and restore your water's clarity, initiate a shock treatment. Use chlorine or bromine granules to raise the free chlorine or total bromine level above 10ppm. For a 1,000L hot tub, this typically requires a 50g dose. Leave your hot tub cover off for at least 20 minutes after this treatment to avoid damage to pillows and cover burn.

    • After a few hours, you should observe an improvement. It's also essential to clean your hot tub filters at this stage to remove any dead algae from the water.

  2. Drain and Refill:

    • If the water proves stubborn and refuses to clear, you may consider a full drain and refill. When refilling, add chlorine to reach a level of 5ppm. Wait for an hour and then use a pipe flush to clean out the pipework, effectively combating any lurking algae in the system.

    • If you're concerned about metals in the water, consider using a pre-filter such as the Hot Spring Clean Screen during the refill to eliminate metal content, preventing a recurrence of the green tinge.

Tips to Prevent Green Water in Your Hot Tub:

  • Maintain ideal water levels: Chlorine/Bromine 3-5ppm, pH 7.2-7.6, Alkalinity 80-120ppm.
  • Use a pre-filter when filling your hot tub if you're worried about metal content in the source water.
  • Keep your filter clean and degreased with a filter cleaner, as proper filtration aids in sanitization.
  • Periodically drain your hot tub every 3-4 months and use a pipe flush to eliminate biofilm, ensuring your water stays clean and inviting.

By following these guidelines, you'll keep your hot tub water pristine and free from the frustrating green hue, ensuring enjoyable and safe soak sessions. 💧🛁 #HotTubCare #GreenWaterSolution

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