Australia's Science Forum

We have recently purchased a Vertex water deioniser, can anyone tell me why when I have tested the pH of the water today it is has a pH close to 9. I did test it when we first installed it and it was around 7.

Thanks for your help.

Vicki

I take it it's using the same water source? Is the cartidge due for replacement? Not much else changes on them!

Richard

I've only had the unit for about 3 weeks, and haven't really used it. Iv'e checked the monitor and it tells me that the water is o.k.

Vicki

What's the pH. of the water entering the unit? Does it correspond to the de - ionised water?

If the filter is recently purchased, as you have said, it should not need a filter replacement. Did you double check your pH reading?
Did you use pH test paper or a data logger type probe to test it? Except for our very new probe, I do not trust the old ones that have been sitting on the shelf for a few years. I prefer the pH test paper The type with several coloured squares that you must match up.
Having said that, our Vertex filter tends to give results in the Acid range, 5.5 to 6.5 or so.
Are you sure that the container that cotained the water was clean, and rinsed to remove all traces of soap or detergent? Many detergents and cleaning agents are alkaline.
As we also have a Vertex, I would be interested in hearing the solution when you find it.

regards
Ian

I just measured the water before and after my new Vertex filter. (So much better, faster and more reliable than the old still that used to practically drain the town's water supply to make a litre of distilled water, not to mention threatening to blow up on the odd occasion). Incoming water pH7 - outgoing water about 6.5. Our water is so pure here I probably don't even need to filter it except for senior chemistry of course. LOVE my Vertex!!

Julie

My de-ionised water is also acidic(about pH6) but water going in is 7-7.5
Lada

I am not able to test my water prior to it going through the Vertex, as it is connected directly to the tap in my fume cupboard. I think I have worked out my problem, (contaminated plastic containers), although the distilled water has been stored in them prior to my days here.

When filling the container and pouring it into new glassware the pH is around 9 and getting the water straight from the vertex tap the pH is between 7 and 8, using universal indicator solution.

As Goulburn has been in drought for many years now, I too am looking forward to using this equipment instead of wasting water using our 30 year old still.

Vicki

can i ask where you got the vertex from and the cost please

Thankyou Narelle

Narelle,
Our Vertex was $685 from Serrata about a year ago. Ours is a bench top model. I just plug it in when I need it They have an "Under bench" (permanantly connected) model for about $885. There are two filters which cost $85 ans $64 each, which , I guess, need to be replaced every now and then!

regards
Ian

This subject recently came up in another forum, and, along with the Vertex, a Millipore filter was also mentioned. Does anyone have experience with both, as I would like to know the pros and cons between the two. Even if you've got one or the other, any tips appreciated. The kind of info I'm after is initial cost, ongoing costs(ie. replacement filters) water quality, water waste( is there any?) ease of use, etc. etc.
Cheers,
Lisa

Hi All,

Cartridge filters may cause some problems when they are used for the first time after replacement or as a new unit as the Ion Exchange Resin inside has a rinse as the first volume of water is allowed to flow. Discard the first few litres then progress to collect the rest.

Also a good measure to test for the purity of the water is not using pH but Conductivity. The conductivity of distilled or Deionised water is within the range of 0.5 to 3 µs/cm (micro seimens per cm). This is the true measurement for the water you are looking at. If you happen to have a conductivity probe that is great as you can simply find the value) if not it may pay-off to borrow one while you take some time to test the water.

Keep in mind that there could be some leaching of the Ion Exchange Resins from the new cartridge take an independent sample and test this first for pH and see how you go.... Then move towards Conductivity.

Hope this has helped,

Cheers,

Robb.....

I have a vertex filter in the prep room, I replaced the filters only about a month ago and I haven't used it a lot in that time however the last couple of times I got water out of it there is a really strong sulfur smell it really stinks. Does anyone else have the same problem with them.
There are a few different types of filters that can be put in them so I was thinking that maybe it is the type of filters causing the smell. I think the last lot had some carbon in them but when I went to purchase more from our local hardware shop the guy insisted that the fabric looking ones were all I needed. What type does anyone else use for proper filtration?
Estelle.

Serrata sell an Activated Carbon filter (for abour $64 and a Mixed Bed Resin filter for about $85. My understanding is that you need BOTH. The charcoal filter removes sediment, chlorine and organic compounds and the Resin filter removes "ionised disolved solids and gasses" (hence "De-ionised" water. In the lab, we need water that is MUCH more pure than a domestic drinking water filter can provide. The man from Mitre 10 would be used to serving customers that are only interested in domestic drinking water filters. Forgive me for saying it, but I suspect that when it comes to laboratory quality water, he probably doas not have a clue!

Does the sulphur smell come from the new filters or the old? It might be stagnent water in the filter. Did you give it a good flush out for 5 or 10 minutes before you started collecting your water?

regards
Ian

Hi Ian
I think you are right about them selling me cartridges that are suited to home use. I will order the ones you suggested from serrata, I am sure they are the type I originally had.The sulphur smell is with the new cartridges and I guess its because I don't use it every day so it must be because the water sits in the filters. I wouldn't like to use it as a home water filter though the way this smells.
Thanks for the info about filters.
Cheers
Estelle