PUR Ultimate Water Filters (The Big ones)

[babyblues71]

I recently sent a question to the PUR (Competitor of Brita) water filter company pertaining to their "larger" filters which used those new "Ultimate" filter cartridges. Basically, I asked them about phosphates and such and if they thought it was okay to use their filtered water (Not the faucet filters but the slow-drip ones) within a fish tank's water as top-off water for a reef tank. They replied with the following....

We do not recommend that you use filtered water from our water filtration
systems in your fish tank. Our filters can change the pH levels in the water and
this may have a negative effect on some fish. I'm sorry we couldn't be more
helpful.

Therefore, I'm curious. What could cause a pH fluctuation by using this filter? Does anyone know if they use anything "besides" regular carbon in their filters? Sounds as if they may use something else. I've asked, but considering it took me 2 weeks just to get the first reply I'm not going to hold my breath. Therefore, in the meantime I thought I'd leave it open for discussion.

Brent

[koj11]

For what it's worth, I have a PUR ultimate on my kitchen sink. We use this for drinking water and I use it every time for water changes and top off. I have done this for 2 years with no adverse effects.

[dad300]

You might want to ask this question in the chemistry forum. BUt.... It seems to me that when you remove some of/all of the organics the ph of the water would change because the organics contribute in some way to the ph of the water. In fresh water tanks you add peat to lower the ph. JMHO my 2 cents. take it for what it is worth.

[babyblues71]

I've been running a nano-reef for about 3 weeks now and, at first, I was using a slow-drip (Refigerator kind) Pur Ultimate water filter for top-offs with no ill effects. Well, after reading several posts I heard that RO water was supposed to be better, so I started using the "heavily purified" RO Aquafina water that they sell. Well, now I'm getting a light greenish-brown slime-film on the sides of the tank that I wasn't getting before. Therefore, I'm kind of wondering which is "truly" worse now. I'm in the process of buying a TDS meter so that I can test different types of water out of curiosity to see which really has more of the "bad stuff." I realize that it's possible that a water with less TDS could still have the "worst" elements for our reef tanks in it, such as phosphates, etc. when compared to say, something that had more TDS. However, I would think, overall, the less TDS the better because there'd be a "less likely" chance of having things such as phosphates within the water itself. Anyway, in the meantime I'd really be curious to know "what" PUR filters might have in them which could contribute to a pH change.

[jjmg]

They may have been replying for freshwater tanks. If you use RO water for freshwater you have to add back many of the minerals that has been stripped away.

[john76]

Aren't the pur filters just carbon?

[manderx]

i think there is some sort of silver-based media in them (in addition to carbon) that picks up heavy metals better than carbon. but i could be wrong.

[babyblues71]

I just received another post from PUR. Here's what it said....

The composition of the Pitcher filters is granulated carbon and the Faucet
filters is a solid carbon block. Our filters also use ion exchange resin to
remove heavy metals and this is what accounts for the change in PH.

Hope that helps.

Marc
PUR Team

Back to me....Therefore, that explains what they meant by possibly causing a pH change. Now, what interests me is the fact that there's basically 3 different types of filters that PUR uses. Plus, Advantage, and Ultimate, with Ultimate being the best. Also, there's two different types of filters overall--faucet mounts and slow-drip mounts. Maybe it's just me, but I would think that the slower the filtration, the more likely contaminants would be cleansed because it takes the water a longer time to exit the filter. Which is why, I think, conflicting reports are apparent concerning the TDS of PUR filters. Now, one also has to take into consideration what the TSD's of their water was "beforehand", of course. Anyway, I ordered my TDS meter today, and will let anyone whose interested know the differences between Wal-Mart distilled water, Aquafina, and a large container PUR Ultimate filter using Tampa, FL. tap water gives as far as numbers are concerned once it arrives. I know that Aquafina will probably test out the best since it's supposedly RO water, but I'm really curious to see the difference between Wal-Mart distilled and filtered Pur water through its best, slow-drip filter. I also found the following message on Reefland, which I thought was interesting....

(I believe) the PUR water filters, actually have DI resins in them that should clean the water fairly well. The problem is that you really don't know when the resins are exhausted. The mechanical indicator is based on the volume of water flowing through the filter (I think) and not if the filter is actually exhausted. Some things like chloramines can really do a number on a DI filter and can exhaust it faster than it's rating.

Of course, a lot of this is off the top of my head and I would have to research the actual filters more before I could venture a better guess....

-Mike

[zanemoseley]

It sounds like to me they're using a small Deionized cartrige, you could get a TDS meter to tell when its exausted.

[babyblues71]

Here's the interesting results. I just received my TDS meter...

Pur slow-drip filter using the Ultimate cartridges--264 DO

Brita faucet filter-367 DO

Tap water (Tampa, FL)-387 DO

Aquafina bottled water (Made via a really complex RO process)-4 DO

Aquafina is, of course, the preference for those of us who have pico-reefs and don't need a slew of water for top-offs. What "was" interesting, however, was the fact that the slow-drip filter had around 100 less DO than the "instant" faucet filter. Also note how the faucet filter was basically useless when compared to tap water. Only a 20 DO difference! Anyway, I always figured that the slow-drip filters were better than those "instant-on" faucet filters....

Brent