Sterilising a Well and UV filters

Cork Rebel

Hi guys,

New to the forum but have been reading it for a while, it seems like a good spot with plenty of helpful people.

I sunk a well about 2 years ago, I sterilised it myself a number of times with hydrochlorine (I could be wrong with the name), but each time I got it tested there were choloforms and ecoli showing up.

My questions are:

Does anyone know what amount of hydrochlorine I should be using (I know from doing searchs on the internet there is a formula, but I was never very good at maths), each time I sterilised the well I used about a half gallon and the last time I used a gallon but there was never a very strong smell from the taps so I was thinking that I didn't use enough.

Also at this stage and hopefully depending on yer advice I am thinking of getting a UV filter, does anyone know where I can a good quality one at a good price, maybe on the internet. I have been quoted between €750 - €950 for supply and fit.

I look forward to your advice.

Thanks

Rebel

CJhaughey

I found one from this shop on ebay
http://stores.ebay.co.uk/Meare-Solutions_W0QQcolZ4QQdirZ1QQfsubZQ2d999QQftidZ2QQtZkm
The model I was looking at was a sterilight round £200 for the model I wanted, ask him about them because I don't see them on the website now.

Cork Rebel

CJ,

Thanks for that information, do you mind if I ask a few more questions?

HGw do you find the UVF filter supplied, has it improved your water?

Did you fit it yourself, was there much to fitting it? How big is the unit (approx)

Did you do a bit of research on the web, did you find this to be the best product or was it the only one you came across?

Does the unit fit under the sink for one tap only or can it be fitted in the pump house to sterilise all of the water going to the house?

Thanks for your help and apologies for all the questions.

Thanks

Rebel

Pocari Sweat

Cork Rebel wrote:

CJ,

Thanks for that information, do you mind if I ask a few more questions?

HGw do you find the UVF filter supplied, has it improved your water?

Did you fit it yourself, was there much to fitting it? How big is the unit (approx)

Did you do a bit of research on the web, did you find this to be the best product or was it the only one you came across?

Does the unit fit under the sink for one tap only or can it be fitted in the pump house to sterilise all of the water going to the house?

Thanks for your help and apologies for all the questions.

Thanks

Rebel

Just back to your original question, the sterilising agent is known as hypochlorate, commonly known as Milton fluid when bought off the shelf normally in concentrations of 2%, then diluted down.

Free chlorine or the chlorine found in diluted hypochlorate has to be between 0.1 parts per million to 0.2 ppm to be effective but not detectable to the nose and pallet. Any level above this may become objectionable in water.


Good Ultra Violet sterilisers for domestic household use should be around a 5 gallons per minute specification and run at the UV wave length of 254 nanometres.

They cost 500 euros fitted for a good brand or up to 800 euros for larger 10 gpm units.

The water can be tested afterwards by taking a sample to a Hospital Pathology laboratory that tests public water supplies.

They give out free 500 ml sterilised sample bottles, which you need to fill with the UV sterilised water and return for testing, for approx 25 euros.

Make sure you run the kitchen cold tap for 5 minutes, then fill the sample bottle to the neck till its overflowing and tighten on the cap. Get the sample back to the lab same day, preferably by lunch time, early afternoon.

Fitting a UV is simple enough, but a delicate operation with regard to handling the UV bulb or quartz sleeve if separately packaged.

They need to be fitted with a 5 micron prefilter and have to go on a naturally or artificially soft water supply.

Any limescale in the water will scale up the quartz sleeve and render the UV system useless within a short period of time on hard water.

They are around 10" to 20" in height depending on make and model.

Some are neatly presented in all in one housings, others have a separate ss reaction chamber, separate electric ballast, separate filter housing and messy wiring. These models are easily found for 500 euros DIY and some firms may fit for this price, but not many.

The posher models are all in one units and are a few hundred extra, but are neater looking.

Always fit at point of entry to all household water for best results, in pump house preferably.

Cork Rebel

Hi Pocari,

Thanks very much for your reply, you seem to know a lot about it, you must work in the business.

Is there any filter that you would recommend? What about buying on the internet, do you think I would get it cheaper?

The 5 micron prefilter, is this part of the UVF filter or is it seperate, any idea how much this costs?

How often do you need to change the UV lamp?

And finally do they work?

Thanks for your help.

Rebel

Pocari Sweat

Most UV units are fairly infallable, it is just the UV bulb that does the work and the only other selling points are the grade of stainless steel (312, 316 etc) and the quality of the ballast, hours counter, other features etc.

A decent UV, with 5 micron prefilter and all necessary bits would be Aquapro or Sterilight, for around 500 euros.

They work to about the highest efficiency of any type of filter on the market. Your typical RO actually has nitrate and sodium removal figures listed at the 85% to 95% range even for some of the better RO filters and these work on the ultra/nano filtration range of particles.

Other physical bacterial filters such as sub micron ceramic filters even get up to 99.9%. But when it comes to UV, if they are properly installed and put on soft water / softened water, with no turbidity, they have bacterial killing efficiencies of something between 99.9999 and 99.999999% which means it would take sometime for the health board, regardless how strict their tests are, to find a plate count of even 1 e.coli. let alone some of counts of 50 or so you see in the worst wells and group schemes.

They need a new bulb every 12 months. After 12 months or 8766 hours of use, their efficiency starts to decline, but in effect they keep on going, so dont worry if you are a day late in fitting a new bulb.

Most operate on 30 watts of power, the larger ones take a little more.

Cork Rebel

Hi Pocari,

You are a well of knowledge (excuse the pun).

Just a couple of questions:

What does RO stand for?

What do you mean when you say "soft water / softened water, with no turbidity". Does this mean that in addition to my UV unit, do I also have to get something to soften the water. I have a domestic well.

As said earlier I have sterilised the well a number of times. Do you think there is any point in sterilising again before I spend on a filter, or would you recommend fitting the filter. Would I have to sterilise the well when I have fitted the UV unit.

Would it also be worth considering sinking a new well, I know that there would be no guarantee that this supply would be free from e-coli or choliforms but is it an option worth considering or would the UV unit in your opinion be the right option.

You have some knowledge on this matter, are you in the business and if so do you supply these filters and replacement tubes, or would you recommend anyone.

Thanks again for your help.

Rebel

Pocari Sweat

Corking stuff there Rebel.

RO stands for reverse osmosis, or under sink high quality filter usually for chlorinated or sanitised supplies, but can be used on well water with the right precautions taken.

Soft / softened water... Water usually has dissolved limestone rock in it, which makes the water hard. Most water in rural ireland is hard to some degree, but the odd source from say rivers, lakes, run offs/springs from granite mountains may be fairly free of lime or "soft".

Softened water, is hard water that has had the lime taken out of it usually by a salt based water softener. An RO is essentially a lime removal filter, but does not like to be run on hard water supplies over 171 ppm of lime, and is often fitted after a water softener or UV filter.

Turbidity is any form of fine sediment or silt or iron precipitate etc that can cause the water to become cloudy, and therefore the operation of a UV - running on an Ultra Violet lamp, with bacterial killing rays needing clear water for the UV light to shine onto bacteria and kill its reproductive DNA, means that any cloudiness will make a UV ineffective.

Also hard water may scale up the outer quartz sleeve of a UV, so the water needs to be soft enough and free of turbidity for a UV to work.

A lot of established firms will sell almost anything without getting the client to do a proper independent Health Board water test to check all contaminants (parameters) that may cause problems with equipment, and in any case are required to assess what equipment exactly is required.

Once a UV is fitted you only need to run a small amount of milton fluid in yer household pipes for a short while, or leave the UV to flush out the existing traces, but a chlorinating "shock treatment" may get to any nooks and crannies where bacteria may sit - in sediment in parts of the plumbing system, ingress in pipe joints etc, but not too real a concern in practice.

A new well for 2 to 3 k euros may be worse than the old one. A UV will guarantee to lots of decimal places, major eradictaion of wee nasties.

A well that is bug free, then may get bacterial ingress later on. Well water is the wildest and most prone to change ye can get as there is no guarantees what the next field or two, next to you where water sinks through into the rock stratas below, has in the way of animal shiite, fertilisers etc.

PM me for a good UV system anywhere from 500 euro, ready to fit for a standard to large size house.

Cork Rebel

Hi Pocari,

I have sent you an pm.

Just one question because it is a new house there are some rooms where the plumbing hasn't been completed, i.e. no sink or taps in a bathroom. When I sterilised previously I didn't run the water through these pipes could this have resulted in the presence of ecoli adn choloforms. I suppose what I am saying if everything else was ok but these pipes where never sterilised can they recontaminate the rest of the supply again?

Thanks

Rebel

Pocari Sweat

Don't worry about new pipes and poss bacteria. If copper pipes are installed with soldered fittings, it would be worth having the plumber to do a final flush with a chemical cleanser to remove excesse flux etc. Not generally done, but should be.

Cork Rebel

Hi Pocari,

My concern with the pipes not being used was that the bacteria in them not having been sterilised could contaminate the sterilised supply.

Another couple of questions, if you don't mind:

I don't notice it as much now but before when I'd run the tap I used to get a gassy smell. Any idea what this might be?

Also when I boil the kettle there are little specks in the boiled water. They are slightly brown/cream in colour, wafer thin, hard and brittle. Is this lime? I live in a limestone area, even though when I got the water tested the results showed that the water wasn't that hard.

Thanks again for your help.

Rebel

Pocari Sweat

Gassy smell could be hydrogen sulphide if it a bit like rotten eggy smell or ammonia. These can be sorted out either by using a KDF 85 media or CrystalRight media.

Specs sound like limescale, but what level of hardness was noted, if over 50 ppm then there will be slight poss. moderate hardness.