Comment by gnulinux | Hacker News Reader

Comment by gnulinux | Hacker News Reader

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It seems to me like the biggest concern (at least this is the case for me (a layman) and my girlfriend (a PhD candidate studying Chemical Biology)) for us is that building infrastructure that uses PFA-based materials increases the chances of them ending up in water or food.

For example, I used to drink tons of unflavored, purified carbonated water (aka "Seltzer Water"). I thought this is likely not very unhealthy since it's literally just pure water + carbon dioxide dissolved in it. It made me drink tons of more water (we're talking significantly more water than I would normally drink) so I thought it's a net benefit. But some evidence came out [1] that common seltzer brands have detectable amount of PFA in them. This may be because (1) PFAs are in water sources, (2) PFAs are in the plumbing systems of these companies' factories, (3) something else. Since we don't know how much PFA is too much, we've been a lot more meek about drinking seltzer water. To be honest, I still do drink it, but a lot less so. I mostly drink tap water, and in the area I live in (Boston, MA), there is no PFA detection, or it's very low.

[1] https://www.cbsnews.com/news/pfas-chemicals-in-sparkling-wat...

Aside from the PFA situation, it's possible to turn your tap water in to selzer water (probably generating less waste and saving money) with a SodaStream or similar.

Yes, and get an RO system to remove PFAS first

SodaStream is much better for the environment, but it’s also really not the same thing.

I was so disappointed when many of our local restaurants stopped serving bottles of San Pellegrino, and instead switched to whatever the commercial food service equivalent of a SodaStream is.

This project [1] is about replicating various mineral waters at home. They have a spreadsheet with chemical analysis of many different bottled waters, and a calculator where you can get your own tap water analyzed and calculate what to add to go from your tap water to Pellegrino, or your preferred mineral water. I haven't tried it yet, but as soon as we get our home carbonation system up and running, am looking forward to it.

[1] https://khymos.org/2012/01/04/mineral-waters-a-la-carte/

If an approximate match is good enough, you can use "Burton salts". It's a blend of salts sold at homebrewing suppliers, matching the mineral content of water from Burton upon Trent, which is famously good for brewing hoppy ales, and which tastes very similar to San Pellegrino.

You can get a zip hydrotap that dispenses carbonated water from a standard built-in tap.

It’s “real” carbonated water and is also chilled. It works quite well.

Further, it has standard tank hookup so you can attach a huge co2 tank if you prefer. We only have to change it out yearly.

The tap water here in Barcelona contains so much chlorine that it smells like a swimming pool after I shower lol. No way I'm drinking that even filtered.

A semi-decent under-sink reverse osmosis system can remove the vast majority of chlorine from drinking water. If it's as bad as you say, I highly recommend the investment!

Scam. While you are at it any timeshare you can also recommend? Or get rich quick from bitcoin scheme?

RO works, but like any solution there are pros and cons

I'm aware it wastes an unfortunate amount of drinkable water. I'm also aware it filters things that might be beneficial, fluoride being one of them. I regret the water usage but I feel it a better alternative to poor health or bottled water, and I use high-fluoride toothpaste to compensate.

Are there other cons I'm not aware of?

energy consumption

My RO system works purely on water pressure and requires no electricity. Do you mean the increased pressure causes increased power consumption?

Water Pressure is a form of potential energy, like rolling a ball up a hill. The RO system is high pressure on the raw side and low pressure on the clean side - the difference in pressure is the consumed energy.

Right that makes sense, but if that’s a serious drain of energy then one would imagine clogged pipes cause dramatically more waste?

Seems like small potatoes compared to having clean drinking water.

Fair point. At utility scale the power requirement is non-trivial. Like anything, there's more than one way to do it, and there's pros and cons to everything. It's up to the owner to decide what they're comfortable with :)

I understand that the difference in pressure at the inlet and outlet of the RO system indicates that work was done moving the water through the system, but the RO system is there to fill a glass of water - it's not clear to me why the outlet pressure is relevant.

Are you saying that the amount of energy it takes to deliver a given volume of water, varies based on the resistance at the outlet?

This poster is in Europe - like most of the rest of the world, they don't have to worry about fluoride removal from water because it's not there in the first place.

Most toothpastes make my teeth sensitive. Interestingly, one of the few that doesn't is fluoride-free. There's been no negative difference in the health of my teeth over the last several years of using that. My experience - fluoride overhyped, especially if you have an electric toothbrush.

You possibly have healthy enamel. I do not - and fluoride has been shown in many studies to prevent tooth decay.

It’s also a heavy metal, so if you don’t have problems with tooth decay I’d say you have nothing to worry about :)

Fluoride isn't a metal!

I'm from Europe and I got several fluoride treatments as a child, with fluoride gel applied for a few minutes. I'm nearly 50 now and I ony had a couple cavities :) So it seems to work. And it's in some toothpastes too. It doesn't have to be in the water.

Counter top ro systems like aqua tru waste very little water, and you get to keep the waste water, eg to water plants

As grumby said, the energy consumption. Power is consumed as the water is forced through the membrane. As the membrane blinded off, more energy is required for the same amount of water.

Filters are very effective at removing chlorine.

Activated carbon filters will adsorb all contaminants including chlorine. Eventually the adsorption potential is consumed and you have to replace the filter. It's cheap and gold-standard effective.

Water utilities will all be moving to activated carbon filtration as emerging contaminants are better understood and regulations catch up.

Get a tank of CO2 and make your own.

Sadly, you can’t replicate San Pellegrino using tap water and a co2 tank.

You can come close, using distilled water and some powdered minerals that are available at homebrewing supply stores:

https://www.homebrewtalk.com/threads/san-pellegrino-clone.56...

finally dehydrated luxury water

See my comment upthread… zip hydrotap. It’s closer to that German brand that starts with a ‘g’ but every bit as “real” as San pelligrino

You mean Gerolsteiner? Also, what Hydrotap machine are you referring to specifically? Zip HydroTap G5 CS? Just having this discussion with my wife and am researching options. Thanks!

I am in the US ... we have a "HydroTap Arc BCS":

https://us.zipwater.com/hydrotap-product-range/hydrotap-arc-...

A lot of people are complaining about SodaStream et al due to mineral content but my complaint is actually different! I prefer purified water anyway (I don't need the minerals for taste, tap water is good enough). I have a soda maker at home (it's not gas-based SodaStream-like, it creates CO2 through baking soda and citric acid). However, these do not carbonate water as much as Polar or Canada Dry seltzer waters. I like it when my water is maximally carbonated, it almost burns my tongue. Half-carbonated water tastes gross, it's like someone opened a can of seltzer and let it sit for 30 mins...

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