
Quick overview
- Lanthanum chemistry PhosFree is built on lanthanum, a rare earth compound, rather than a flocculant.
- Works at the filter Added to the skimmer, it forms a thin coating on the filter media that strips phosphate as water passes through.
- Stays clear It is formulated to lower phosphate without leaving the water cloudy.
- Three liter size The larger bottle, for a full initial treatment rather than a single small dose.
- Any pool Listed for above ground, in ground, residential and commercial pools.
- Part of a routine Once phosphate is at 100 ppb or lower, Natural Chemistry moves you to a weekly maintenance product.
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Product details
PhosFree is Natural Chemistry's phosphate remover, here in the 3 liter bottle, part number 05121. It is built on lanthanum, a rare earth compound, and it does its work inside the filter rather than in the body of the water.
How it works
You shake the bottle and pour the dose into the skimmer with the filter running. A thin coating of PhosFree forms on the filter media, and as pool water passes through, phosphate is pulled down to very low levels. Because the reaction happens on the media, the pool does not go cloudy the way it can with other phosphate treatments.
Getting the dose right
Treat any algae first, balance the water, and clean or backwash the filter before you start. Then set the dose from the chart using a measured phosphate level, which your dealer can give you accurately. After dosing, run the filter 8 hours a day for a week or 48 hours continuously, and do not backwash or clean it during that window. On a DE filter, if pressure climbs above its normal range, bump the filter per the manufacturer instructions and restart until pressure settles.
Keeping it there
Once phosphate reads 100 ppb or less, the program moves to maintenance: a weekly dose of Pool Perfect+PHOSfree at one cap, 4 oz, per 8,000 gallons.
| Brand | Natural Chemistry |
|---|---|
| Manufacturer part number | 05121 |
| UPC | 717108051215 |
| Chemical type | Phosphate remover |
| Size | 3 liter |
| Active chemistry | Lanthanum (rare earth) compounds |
| Application | Shake well, add to the skimmer with the filter running |
| Filtration after dosing | 8 hours a day for one week, or 48 hours continuously, without backwashing or cleaning |
| Pool type | Above ground, in ground, residential, commercial |
| Shipping weight | 7.65 lb |
| Ships | Parcel |
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