Pozzani filter: Update and more Qs.


Feb 16, 2008
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5 months in and the Pozzani filter remains my preferred method for dealing with high nitrates in my tap water (50ppm).
Only 2 downsides are:
  1. My first attempt at recharging the resin was unsuccessful
  2. Relatively short cartrige life - typically 4-6 weeks filtering 125 liters per week
The cost isn't a huge deal but I have purchased some refillable cartriges so I can remove resin to try to re-charge it. I have also ordered a couple of cheap housings so it would be easy to set up a multi stage filter - and if I am running it through a filter already there is no extra effort in passing it through additional filter(s).

Much of the reading I have done suggests that the nitrate filter is more effective (and longer lasting) if the water is de-chlorinated and pre-filtered first, which makes sense. But the Pozzani website suggests that if you are using a dual filter you should use a carbon block after the nitrate filter. I don't understand their logic unless its to preserve the life of the carbon filter. So far I have been filtering chlorinated water and putting it in the tank with no further filtration so I am proposing to use the carbon filter first unless any one has a good reason not to.

There is another reason for the question. Recently I looked at mixing RO water to reduce the hardness. I decided not to go ahead with this but I have discovered this on the Pozzani website https://www.pozzani.co.uk/product_info.php?products_id=184. I have ordered a cartrige to fit in one of my spare housings. Again their recommendation is to use ths BEFORE the carbon filter. But AFAIK this type of filter is typically used to polish the water after RO and the resin will be depleted very quickly if used directly on unfiltered tap water.

So my full proposal is:
  1. Create a 2 stage filter using activated carbon block and nitrate reducing resin in that order. All my water will go through this filter
  2. Create a standalone softening filter and daisy chain this onto the end of the dual filter for the amount of "soft" water I want to mix in
Finally is there any reason to think the softening filter is anything other than standard DI resin. I won't be trying to re-charge this, but if so it may make more sense to buy the colour changing version for an easy life :)


May 13, 2011
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Central New York, USA
Although the typical resin used to adsorb nitrates from source water is rechargeable with a brine solution, I don't know of a way to recharge DI resin.
I use a commercial inline activated carbon filter AFTER my DIY de-nitrate filter (that uses API Nitra-Zorb), but I do not have chlorine in my well water.


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