By Natural Chemistry



Model # 05221

Alternate Part #'s NAT-50-920, NC05221EACH, NCH15221NCM

Product Description

Natural Chemistry PHOSfree 2 Liters - Zero Phosphates, Zero Problems

PhosFree is the only patented product on the market that removes phosphates on the filter. Its easy application into the skimmer will not cloud your water.


  • Reduces phosphate levels to near zero
  • Will not cloud pool water
  • Easy to use, just add to skimmer
  • Non-toxic and will not harm the environment
  • Compatible with all sanitizers and pool surfaces

Dosage:Per 10,000 gallons (38,000L)

Phosphate Level (ppb)  Phosfree 
 300 or less  16oz (0.5L)
600   32oz (1L)
 900 48oz (1.5L)

How to Apply:

  1. If pool has algae, follow dealer instructions to treat
  2. Follow dealer instructions to balance water chemistry
  3. Clean or backwash filter, if necessary
  4. Determine required PHOSfree amount (see above chart)
  5. SHAKE BOTTLE WELL, with filter running add required dose directly to the skimmer -Note: If DE filter pressure rises above normal range, bump filter or if there is no bump option turn filter off for a minimum of 30 seconds. Repeat either procedure until pressure remains in normal range
  6. Run filter 8 hours/day for 1 week or 48 hours continually without backwashing or cleaning
  7. When phosphate levels are below 100ppb, start weekly dose of Pool Perfect+PHOSfree


  • Add 1L (33.9oz) at a time to DE & Cartridge filters to avoid increased filter pressure.
  • It is important to retest phosphate levels after completion of a phosphate treatment.
  • Repeat PHOSfree treatment until phosphates are 100ppb

Features & Benefits:

  • The only patented phosphate remover that works on the filter
  • PHOSfree is formulated from lanthanum (rare earth compounds).
  • Will not cloud pool water

For our complete line of Natural Chemistry Pool & Spa Chemicals

Product Specifications

2 L
Pool Type:

?     Asked on 10/18/2012by Guest

I've been told that my pool water is high in phosphates. I have used a phosphate remover to lower the levels but they were high again shortly thereafter. Am I doing something wrong?

A  Answered on 10/18/2012 by InyoPools Product Specialist Patrick P.

There are several reasons why the phosphates can increase. Certain pool chemicals contain phosphates. Fertilizers and pollen can add phosphates into your pool too. You may need to drop down the phosphates as low as you can and use a phosphate remover on a weekly basis for maintenance.

?     Asked on 11/27/2012by Guest

Will using Phosfree raise my filter pressure?

A  Answered on 11/27/2012 by InyoPools Product Specialist Patrick P.

Phosfree raises the filter pressure because it puts a coating on the filter media (sand, d.e., or cartridge) so it is able to catch the phosphates. After an 8-10 psi increase in the filter pressure, the filter should be cleaned or backwashed.

?     Asked on 12/20/2012by Guest

I used a phosphate remover in the beginning of the pool season. Now in mid-season, it seems like my phosphate levels are going up. What can I do?

A  Answered on 12/20/2012 by InyoPools Product Specialist Patrick P.

Phosphates come from several sources. If you use fertilizer on your lawn or if you use well water to fill the swimming pool, you are more likely to have a recurring phosphate issue. I would recommend using Phosfree on a monthly basis to keep the levels low.


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 (Average 4.86  out of 5 stars)
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