paul spector Posted February 21, 2007 Report Share Posted February 21, 2007 My pool man tells me the entire water supply should be changed every seven or eight years because it accumulates calcium that will clog the filters. Is this a valid recommendation? Quote Link to comment Share on other sites More sharing options...
waterbear Posted February 21, 2007 Report Share Posted February 21, 2007 My pool man tells me the entire water supply should be changed every seven or eight years because it accumulates calcium that will clog the filters. Is this a valid recommendation? Water in a pool does not accumulate calcium. The calcium has to be added either by adding calcium chloride to increase calcium hardness if it is too low, by chlorinating ith calcium hypochlorite, by having a lot of calcium in the fill water used in the pool, or by letting your water balance go out of whack so you literally dissolve some of the plaster finsish of the pool (for a plaster pool). If you are chlorinating with calcium hypochlorite there is a simple solution...use sodium hypochlorite or lithium hypochlorite instead! If you fill water is very hard (high in calcium) then draining and refilling isn't going to help much unless you fill from water coming out of a water softener. If you accidently added too much calcium hardness increaser just drain out some of the water and refill. If you let your water chemistry get so out of whack that you are dissolving calcium from the plaster then fire the pool man and get one that knows what he is doing! (Or better yet, learn to take care of the pool yourself!) More serious problem (and I am surprised your pool man didn't mention this!) is if you are using trichlor or dichlor exclusively....your CYA (cyanuric acid or stabilzier) will rise to unacceptable levels. This will cause the chlorine to become in ineffective sanitizer and allow algae outbreaks and it has been found by reseach recently done by Arch Chemical (HTH and PoolLife brands of pool products) that high levels of CYA will damage plaster pools! I have seen pools that use cartridge filters (which are not backwashed) go from 0 ppm to above 100 ppm (way too high) in one year or less and pools will sand filters in a few years time! BTW, some might blame this on TDS (total dissolved solids) but that is not the case. It is not the total amount of stuff dissolved in the water that matters but WHICH stuff is contributing to that total. For example, a pool with a lot of sodium and chloride ions, while having a high TDS, will not have any adverse effects (or pools with salt water generators would all be in trouble) but if the measured TDS is coming from sulfates from using dry acid and non chlorine shock then you run the risk of plaster damage and if it is coming from high calcium you can develop scale deposits on the pool and in the filter. Quote Link to comment Share on other sites More sharing options...
Pool girl Posted February 21, 2007 Report Share Posted February 21, 2007 it really depends on where you live. and what yout total desolved solids are. calcium (if in good balance) would not have an effect because it is linked to the pool chemisty. you have heat and your water evaporates out a lot, then you are constatly replacing water, especially inteh summer time, and your TDS does not increace. but if you are in a place where it doesn't rain or the sun doesn'ty evaporate your water out then you do have to change it about 10 years or so, but it all depends on you TDS level. i think it can go up to 2500 ppm. before it will stop taking shemicals. also if your CYA is high then you would also haev to drain your pool to get that down or youse a chlorien shock that does not have it in there like calcium hypochlorite or liquid chlorine. hope this helps. pluss your filter sand is changes every 3-5 years so it cann't clog your sand filter. Quote Link to comment Share on other sites More sharing options...
waterbear Posted February 23, 2007 Report Share Posted February 23, 2007 it really depends on where you live. and what yout total desolved solids are. calcium (if in good balance) would not have an effect because it is linked to the pool chemisty. you have heat and your water evaporates out a lot, then you are constatly replacing water, especially inteh summer time, and your TDS does not increace. This is not true, some -parts of the country have water with very high TDS! Sometimes so high that water is trucked in. If the pool is topped off with water that has higher TDS then the initial fill water then the TDS will increase with each topoff. but if you are in a place where it doesn't rain or the sun doesn'ty evaporate your water Only place I can think of that meet these two requirements would be the dark side of the moon. out then you do have to change it about 10 years or so, but it all depends on you TDS level. i think it can go up to 2500 ppm. before it will stop taking shemicals I would suggest to learn exactly what TDS is before you try to give someone advice about it. Your previous statement is totally false. A pool with a SWG (salt water generator) that uses a salt level of, say 3200 pppm such as the Goldline units, would have a TDS of higher than 3200 pppm, perhaps much higher and yet many more ionic substances could still dissolve in this water. This is what Total Dissolved Solids means--the amount of ionic substances DISSOLVED in the water (as opposed to non ion susbstances or suspended particles). . also if your CYA is high then you would also haev to drain your pool to get that down or youse a chlorien shock that does not have it in there like calcium hypochlorite or liquid chlorine. You should NEVER shock your pool with stabilized chlorine. It will cause a very fast rise in CYA! How high your CYA is will determine just how high you need to shock and how high you need to keep your FC for normal sanitation. hope this helps. pluss your filter sand is changes every 3-5 years so it cann't clog your sand filter. Filter sand won't clog your sand filter....calcium desposits and dirt clog it. Sorry to sound harsh but there is enough bad advice in this industry from 'professionals' and manufacturers trying to sell products (some of dubious value) so that someone who really has little understanding of pool chemistry but knows a few terms (but not their meanings) should really not try to give advice about things they really don't understand. Quote Link to comment Share on other sites More sharing options...
DKN1997 Posted March 4, 2007 Report Share Posted March 4, 2007 My pool man tells me the entire water supply should be changed every seven or eight years because it accumulates calcium that will clog the filters. Is this a valid recommendation? What type of pool do you have? If it's vinyl liner, good luck changing the water after it's been installed for 8 years. When it's empty and you start filling it up, the sun will shrink it up and you will have some nice windows in that liner. I don't really see the logic in changing the water unless a very detailed water test indicates that draining must be done. as far as calcium clogging up the filter, I don't see that happening if your calcium levels are kept at proper levels regulary. that's not to say your pool guy is totally off base, plenty can happen to a filter in 8 years. sand wears out, (if you rub it between your fingers and it's smooth,it's done) DE elements start ripping, cartridges rarely last 8 years without replacement. I have seen calcium clog up the filter, but only when calcium hypochlorate (granular shock) is added to the pool through the skimmers over a period of time. I say if it looks good and the water tests check out, don't drain it. Quote Link to comment Share on other sites More sharing options...
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