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Nuke it really good with chlorine run everything for a couple of hours drain and refill it, rinse filter really good. Repeat if necessary. And yes all that nasty stuff is coming from the plumbing. If bad enough it may take a couple of times to get rid of it.
Ok, well the info to Nuke it and then to keep it at 100ppm! are one in the same. I think they meant to say 10 ppm...You have tissue mold. It is harmless but truly disgusting looking. It lives in the plumbing so just shocking the water will not take care of it. I am going to send you a sheet on how to treat this condition. Once you have killed it, you will need to drain the spa ( spa purge is a great thing to add after this process) , clean your filters or replace them if they are older than 3 years and start fresh. I can send you a simple hand out on daily maintenance that you can use once this process is complete. Can I send it to you in a PM? Please do not skip over this. Tissue mold is hardy and needs to be totally eliminated from the spas system. Treatment Of Tissue Mold and Pseudomonas Folliculitis Bacteria.A) Tissue Mold: White floating material that looks like facial tissue and dissolves easily.It is always best to make sure your pH and Alkalinity are in balance before you start this process. Using a test strip, balance pH and Alk. then proceed:Step #1) For the Treatment of Tissue Mold: In addition to the filter area this mold lives in the plumbing lines. If your condition is caught early you can rid the spa by shocking the water with Bioguard Enhanced Shock to 10 parts per million (ppm) everyday for 5 days in a row. Start with one tbsp into the filter area with the jets running and check after 15 min. Continue adding shock until you reach 10 ppm. Check the chlorine level everyday and be sure to keep it at 10 ppm. If you have a diverter valve on your spa, run the jets in each of the selectable positions everyday for 20 minutes. Once you have completed the 5-day process, re-clean your filters. We recommend not using your spa while you are doing the heavy shock treatment. Step #2) If the Tissue Mold returns within 2-4 weeks, you need to repeat the shock and supplement the system with a disposable Bromine feeder placed in the filter compartment. REMOVE your Ag+ cartridge (if you have one) during this process. Follow the instructions on Feeder for use. Add one package of Sodium Bromide to the filter with a 10 minute jet cycle. Maintain your spa as usual and remove the bromine feeder in one month. When the process is completed change your water if it is 4 months or older. YOU CAN USE YOUR SPA WHILE YOU ARE DOING THE BROMINE PROCESS. Be sure to use or maintain the AG+ Silver Ion system in your spa to help prevent this problem in the future. When the 5 day process is completed change your water if it's 4 months or older. DO NOT USE YOUR SPA UNTIL YOU HAVE COMPLETED THE 1st PROCESS.
Ok, well the info to Nuke it and then to keep it at 100ppm! are one in the same. I think they meant to say 10 ppm...You have tissue mold. It is harmless but truly disgusting looking. It lives in the plumbing so just shocking the water will not take care of it.