Well Water, Pentek Filters & Iron Oxide

[Sumgod]

Hiya! Any info or experiences you can share greatly appreciated.

Situation: Water supply comes from a well (old brick 'tank' approx two metres deep and one and a half across built over a spring). In the house is a Grundfoss pump, uv light and sediment filter. These and the pipe work to the well were installed 3 years ago, replacing old iron pipe work. The water has been tested and the supply is fine.

The problem (if there is one) is that the Pentek sediment filter gets clogged up after a couple of weeks (supposed to last 12). It turns an orangy brown (iron oxide?). I've also found and netted filaments of the same colour from out of the well.

Currently the pipe in the well has a foot valve and strainer on it.

I've been wondering whether I can provide 'extra' filtration in the well itself. Cleaning would be easier (no draining down, etc) and the life of the sediment filters would be prolonged.

I've considered replacing the foot valve with a floating filter (see link below), but since I'm ignorant about the properties of iron oxide (is it evenly distributed in water or does it settle out?) I'm unsure whether this would have a positive effect.

Finally (and apologies for the long post), does anyone know suppliers of Pentek filters? I've Googled but to no avail. Currently I have t get them from the hooray-henry who installed the system (sub-contract to a building firm) and would rather escape his expensive clutches if possible!

Many thanks - Tony

Pentek:

suction filters:

[Baz]

> Floating suction filters: Tony.Drop Gary King an email @ [e-mail] may well have an element to suit. And will be able to help/answer any questions. Baz

[Dave Liquorice]

I wouldn't expect iron oxide to form filaments, at least not soft or none brittle ones. These filaments may well be an algae or bacteria.

[Onetap]

Built over a spring? Are you certain or is it belief acquired with the house?

The reason I ask is that this sounds like a brick cistern. They were built to collect rain water from the house gutters and paved yards. It's usable 'grey' water, but not suitable for drinking. You could check by putting food colouring, or drain tracing dye in the gutters. I've never heard of a cistern built on a spring, but I'm not Dr. Drivel so don't claim to know everything.

You could consider a sand filter, it would take the coarse particles out and prolong the life of cartridge filter. They are similar to water softeners (i.e., they are water softeners) , but filled with a suitable sand and not resin. The control valve backflushes it at intervals and flushes the debris to drain. There are other types used in swimming pools and aquaria. I seem to recall that green sand was the filter media to remove iron salts.

There's lots of info on the internet from the USA. There are lots of rural wells in use out there.

[Onetap]

What type? A red one, by any chance?

[Sumgod]

>>>> Floating suction filters: >> > Tony.

Thanks Baz! I'll give him a try!

[Sumgod]

Thanks for input Dave. It's probably my description that's misleading. You're right I think when you use the word algae; this stuff is like the stuff we sometimes get on the pond in summer - except it's orangy brown.

Look here:

's my (limited) understanding that the colur is coming from iron in the rocks/ground.

[jim]

supply and iron - presumably if i understand it correctly - your foot valve and strainer sits on the bottom of this brick "tank"? and so sucks up sediments etc and sends to your cartridge filter which bungs up prematurely? - if so could you somehow raise the foot valve somehow to clear it of the sediment IOW allow the sediment somewhere to collect *below* the suction level of the pump?

few bricks and a paving slab?

next prob would be how to dispense of accumulated tank sediments when they build up - but there's ways and means! welcome to private water supplies!!!

for filters - google WESTDALE FILTERS or try looking for filters on Ebay - I think what you use is common enough (is it 10inch?) it's just a matter of finding someone who talks and prices sensibly - NB I wouldn't worry about the pentek brand as long as you get ones that fit your housing(s) and offer suitable filtration.

hope it helps

jim

[Sumgod]

Thanks Onetap! I'll check out sand filters.

Brick tank is built over a spring. I drained it once (bucket and rope) in order to make sure it was 'clean' at the bottom. It was. Just a rocky bottom from which the water seeped out.

The 'well' itself is approx 50 meters from the house. The house or at least parts of it are 500yrs old. I suspect the presence of the spring may well account for the house being here in the first place.

[Sumgod]

Red? No it's black! A Grundfos self-priming centrifugal pump.

[Sumgod]

Pentek:

>>> Floating suction filters:> hi tony - we have had similar (tho lesser) issues with our spring

Jim, thanks for info and advice. I'll certainly give Westdale a look. And you're right it is a 10" one.

As for clogging up the foot valve, that's what I'm not sure about. I could shorten the pipe so it wasn't so near the bottom. Or get one of those floating filters. On the other hand if the sediment is evenly distrubuted thoughout the water, neither of these things would make a difference.

Thanks again Jim!

[R]

If there is space and you have the equipment etc could you not build a separation tank so that water is drawn from the well into another tank to settle or have a Pre-Dose" of U.V or coarser filter before being passed to the filtration for drinking ?

If the foot valve can be suspended around half a metre up some of the problems may well disappear.

[jim]

Pentek:

> >> Floating suction filters:> > hi tony - we have had similar (tho lesser) issues with our spring

given enough time the sediment should drop to the bottom - is your supply very "agitated" - i.e. always stirring sediments up in the "tank"? if so then you could do with somehow removing or lessening the amount of agitation to allow the iron to drop - in our case it is rust and is formed when dissolved iron in the water reacts with oxygen at/ near the surface to turn to iron oxides - so what you could look to do also is encouraging air to mix with your supply and so try to get the sediment to form, then try to calm things down in your "tank" (if they are very agitated currently - gushing stream? etc) so that the sediemnt has time to drop, then take your water via foot valve etc from well above the sediment layer. periodically you will have to empty/wash the tank of the sediments that build up - you will know it's time cos your in house filter will clog too quickly than normal.

not sure what you mean by cloigging the foot valve? - my advice was to raise the foot valve above the accumulating sediments so that when your pump pumps it doesn't just suck the sediemnt through and clog your 10" cartridge filter....

How far off the bottom of the tank does the foot valve sit now?

jim

[Sumgod]

Pentek:

>>> >> Floating suction filters:>>> > hi tony - we have had similar (tho lesser) issues with our spring

Hiya Jim,

Thanks for your time and help.

The spring fills the tank to overflowing (via piped overflow) imperceptibly. No agitation.

As I said the foot valve etc was installed 3 yrs ago. It's only recently that the sediment has become a problem in terms of shortening the usage time of the filters. Taking your point about air and iron oxides reacting, I'm wondering if the 3 yrs is about the time for the oxide to build up in the water around the footvalve (about 9" from the bottom). In which case, as you say, raising the valve will help.

Sorry about using the word clogging! I did mean to indicate the vale sucking up the sediment.

Thanks again Jim!

[jim]

Pentek:

> >> >> Floating suction filters:> >> > hi tony - we have had similar (tho lesser) issues with our spring

Right I'm with you - our tank does build up with "rusty"sediment and every few years it's time to get the buckets and kids out and empty all the cr*p out! - ours tank then has a decent 1-2 inches of river sand put back in the bottom to further discourage turbulence (I expect

- as ours is actually fed from a pipe so falls into the tank).

so for you either time to clean it out OR hoist the footvalve up a bit and see how you go - altho I suspect you will only put off (and make much bigger) the task of emptying the sediments out of the tank * one day*.....

....wild card - could you take the overflow into a second (plastic?) tank and use that for your supply? - let the first do most of the sedimentation work?? just a thought would put off emptying to the max!

cheers jim