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Taylor K-2006 Complete DPD-FAS Pool Test Kit
Lab-grade titration kit for accurate Free Chlorine, Total Alkalinity, Calcium & Cyanuric Acid.
How to Kill Yellow Mustard Algae (The Elevated 60% SLAM Method)
Standard green algae dies easily at regular shock levels. But yellow mustard algae is a mutant strain of photosynthetic diatoms with thick protective outer cellular membranes that easily survive standard 10–12 ppm chlorine shocks.
To eradicate mustard algae permanently without wasting hundreds of dollars on copper algaecides that turn your hair green, you must take chlorine to the Mustard Shock Threshold (60% of your CYA level) and sterilize all pool equipment simultaneously.
0MS MUSTARD SHOCK CALCULATOR
Mustard Algae SLAM Shock Dose Calculator
Enter your pool volume and tested Cyanuric Acid (CYA) to calculate the precise elevated shock level and exact gallons of liquid chlorine required to penetrate mustard spore membranes.
MUSTARD SHOCK TARGET
24 ppm FC
60% of CYA concentrationLIQUID CHLORINE DOSE
3.0 Gallons
384 fl oz (12.5% Bleach)HOLD DURATION
24 Hours
Zero overnight lossEQUIPMENT QUARANTINE
Mandatory
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01The Equipment Submersion Rule (Kill Re-Infection)
Mustard algae spores cling to swimming suits, pool noodles, skimmer baskets, vacuum hoses, and robotic cleaner brushes. While the pool is at peak 24 ppm shock level, toss every single piece of pool equipment, poles, vacuum hoses, and toys directly into the pool water for 4 hours. Wash all bathing suits in washing machines with hot water.
02Remove the Underwater Light Fixture Niche
The #1 hiding sanctuary for mustard algae is the wet niche behind your underwater pool light. Unscrew the single pilot screw on top of the light rim, lift the fixture up, and rest it safely on the pool deck. You will discover a thick colony of mustard algae growing in the dark niche behind the bulb. Scrub it with a stiff nylon brush and squirt liquid chlorine directly inside the conduit.
03Hold 60% Shock Level for a Full 24 Hours
Brush the floor and shady wall corners twice daily. Keep your pump running 24 hours on high. Do not let Free Chlorine drop below your calculated mustard target until an Overnight Chlorine Loss Test (OCLT) passes with under 1.0 ppm loss and zero visible dust.
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Need to Restore Chemical Balance After Shock?
After wiping out mustard algae, you must restore proper pH, Alkalinity, and stabilizer ratios. Use our 0ms dynamic water balance engine to calculate exact chemical additions for your pool.
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