You may well have been misled about spa filter & hot tub filter maintenance & indeed the level of effort required in maintaining your spa & hot tub water quality generally! Don't feel bad about this because we estimate that 80% of all spa & hot tub purchasers are in the same boat. The ‘nice' salesman who sold you your spa or hot tub wants prospective customers to believe that ownership is a totally painless process – they don't want ‘obstacles' to appear that may put people off. And of course it's far more romantic to paint a picture of sipping champagne on balmy nights than dwell on the detail of spa & hot tub maintenance! So let us just say that they ‘play down' the importance of spa filter maintenance, how often they need removing & rinsing, deep cleaning with cartridge cleaner & how long your filter/s will really last.
In fairness, the standard lifespan of a ‘Pleated Reemay Cartridge' spa or hot tub filter is generally quoted as being 12 months or so in the spa, hot tub and pool industry. In reality this is more accurate for a ‘Pleated Cartridge' POOL filter, but the statement has just ‘carried-over' to include spas & hot tubs as well. The filters are made of the same (Reemay) material but there are some significant differences between a Pool & Spa or hot tub environment:-
1. The volume of water ‘per person' in a small domestic pool is significantly larger than in a hot tub – a small family pool with say 20,000 litres of water ‘shared amongst' a family of 6 gives more than 3,300 litres per person, an average six seat hot tub or spa with 1,300 litres of water gives just over 200 litres per person – in other words you would need 100 people in the small family pool to be equivalent to having 6 in the hot tub! Massive difference!
2. The temperature that a hot tub/spa operates at is significantly higher than that of a swimming pool. This creates a myriad of other problems, not least of which is the hot tub's ability to breed bacteria at a much accelerated rate, ‘strip-off' body lotions, creams & spray-tan & remove all that latent detergent still ‘hiding' in your newly laundered swim-wear. Adding coagulant products like foam down, sparkle etc. only serves to increase cleaning frequency and further reduce filter life. A better solution is the use of a scum absorber like the new Zorboid product.
The net result of these factors is that the life of a spa filter is a much harder one than that of a pool filter, it is hardly surprising then that their life expectancy is considerably shorter. Recent research from G.E. Water (part of General Electric) the global company, said:-
“The effective pore size of the filter is gradually reduced as some of the pores become blocked by build up of smaller particles. These deformable particles are generally of a semi-solid nature and are present in the form of a slime or gel like material. If the concentration of these particles is high enough then the element can be “blinded off” which prevents flow. When these filters are washed they only retain approximately 10% of their total filtration value; the average life is two months.”
Perhaps the GE research is looking at the worse case scenario, but it nevertheless clearly supports the fact that 12 months lifespan is unrealistic. Of course, many factors will play a part in just how long your spa & hot tub filters will ‘last' – or more importantly how long they will be effective for.