Now that we know what biofilms are (learn about bio-films here), let's talk about HOW to remove them and prevent their return.

Biofilms can be removed mechanically or chemically.  Mechanical removal using vacuums, wall brushes, scrub brushes, filter cleaners, etcetera, physically remove the biofilm from visible places.

Visible places would be the filter cartridge itself, filter tank, vinyl liner, water line, ladder treads, skimmer baskets, etc. You can physically handle the object that needs to be cleaned.  This is one of the reasons why we as Pool Professionals are so adamant about brushing the pool's surfaces on a regular, weekly basis.  Brushing breaks up and lifts the biofilm off from its cozy environs enabling the chlorine to kill it and the filter to remove it.  Be careful however to regularly clean & chemically clean the filter to remove the accumulations of "filtered" biofilms from the filter media - whether it be sand, DE or cartridge.

Aboveground pools with serious biofilm infestations should consider just changing the filter hoses. Typically, most aboveground pools have 2 - 9 ft. or shorter hoses as compared to well over 100 ft. of buried inground piping.

Keep in mind that biofilms are a direct contributor to chlorine demand, causing the pool to use significantly more chlorine, bromine or biguanides than if none were present.  Remove the biofilm, remove an important component to chlorine demand.

In hard to reach places like pool plumbing lines & inside heaters, biofilms need to be removed Chemically. This is where so much biofilm (and about 99% of the bacteria) accumulates and thrives.  Biofilm is left alone.  It has all that it needs - a surface, moisture, and nutrients floating by. Keep in mind that biofilm doesn't need sunlight - it's not an algae so sunlight is not one of biofilm's needs. Biofilm does need "warm" water - 90 F or better for optimal growth, but as long as it's not cold, the biofilm will survive and grow just fine thank you.

Tried & true products such as natural enzymes (Natural Chemistry® Pool Perfect, Pool First Aid, etc.) "eat up" much of the nutrients and other waste that contribute to biofilm growth thereby stunting it. But as biofilms become more resistant and more proliferate, a new arsenal of products must be considered & used. 

New products such as AquaFinesse™ Pool Pucks are added to the pool skimmer and quite rapidly remove the biofilm from the hidden surfaces.  AquaFinesse™ products have been successfully used in the European market and in industrial applications for several years. As with the physical removal products, loosened & removed biofilm particles must be filtered out of the water then removed from the system entirely. 

After initial application, you will notice that the filter becomes rapidly clogged as the filter traps all of that used biofilm.  Cartridge and diatomaceous earth filters must be chemically cleaned to restore the filter to a proper working condition.  If biofilm removal has never been done before, it may be necessary or even advantageous to replace the filter media - especially in older swimming pools.  These products are completely compatible with all pool care chemical systems (chlorine, bromine, biguanides, ionizers. salt).

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