Your pHin Starter box comes with a mineral purifier, which helps prevent and kill algae but we can’t guarantee it will prevent it!
pHin itself cannot detect algae as they are microscopic plants. It takes roughly 30 million spores to an ounce of water before a human can visually detect an outbreak. Algae require three components to grow: sunlight, water and nutrients.
The two most common nutrients are phosphates and nitrates. If you have too much of either of them in your pool, algae will flourish, overcoming even pHin's mineral purifier from keeping the algae at bay.
If your pool has been tested for phosphates, add a phosphate remover to your pool to keep algae under control. As for nitrates, there is no chemical, which removes nitrates. If your nitrate level is high, dilute the pool water down to lower your nitrate level.