TubTest: Hot Tub Water Testv1.7.5

What changed

• New featureAdded a new 'Salt Water' sanitizer option in setup and settings
• New featureAutomatic adjustment of calcium hardness targets for salt systems

Original release notes

Better salt water support is here!

• New "Salt Water" sanitizer option — choose it during setup or in Settings
• Calcium hardness targets now adjust automatically for salt systems (lower range to protect your salt cell)
• Test and track your salt level, with exact dosing recommendations

Plus reliability improvements:
• More reliable sync across your devices
• Retest reminders now stay on screen until you're ready to test
• Fixed stabilizer (cyanuric acid) dosing when using custom ranges
• Stale results now clear correctly so you always see current readings

Thanks for the great feedback — a salt water user asked for this one. Keep it coming!