Maybe it's your point of view ;)

Was serious, actually. If there's a "secret" I surely would enjoy knowing it.

You can't possibly get CLEAR ice cubes from any water. TDS levels can effect the clarity of ice. Dissolved oxygen is present in all water and consequently when the ice freezes much of this appears as air bubbles in the ice and will impart a cloudy effect to ice cubes to a greater or lesser extent depending on each water supplies dissolved oxygen content. The reason cubes from ice cube trays tend to be clearer is much of this dissolved oxygen has been released when water is poured in the tray. Cold water has a much greater tendency to hold dissolved oxygen. Ice makers have small storage tanks (usually a quart or so of water)to supply the machine. Thus the water tends to stay colder when being fed to the machine keeping much of the dissolved oxygen in suspension. Hence CLOUDY ice cubes.
RJ

Clear enough to read a newspaper through... and magnified too.

A terrible thing it is to be compelled to acknowledge my unworthiness to receive the wisdom of he who is capable of making clear ice. I grieve.

rjh20's advice seems about right. Ice from the ice-maker in the ref. is, indeed, the cloudiest. Same water frozen in ice-tray much better. Same water, boiled first, in ice tray better still.

I'm understanding the dissolved air thing better. I'll figure it out before I'm done.

To be accurate... not clear cubes like glass. A small nucleus of air bubbles in a crescent shaped ice cube (crescent) with the majority of the crescent clear as glass.

But if RJ says it can't be then it can't... except I have one in my hand and I'm looking at my computer monitor through it right now... and it's cold and wet.

I believe you. Just don't understand why yours come out differently from mine.

Under magnification, easily seen the "cloudiness" is simply little tiny bubbles. Also easy to observe cube-tray result better -- as rjh2o said -- and that boiled product better still. Everything points to air content imprisoned during freezing as the culprit. How to eliminate? Oh, the trauma of life without clarity of ice!

Well, I'm at 7000 feet above sea level... does that tell you anything?.

There's always more to the story than we can see through the keyboard. Remember thermal expansion?

Hopefully I'll find a solution that doesn't involve moving. I'm at about 2,000.

I know.....buy a balloon big enough to lift my freezer another mile high! Yes!

Well, if you can't rise to the solution then either get your ice cubes from a high altitude supplier or you gotta live with the cubes ya got.

Here is a chemical physical answer, not a mechanical physical answer.

if you put a drop of HO into the water it will turn into H2O.
In so doing it will remove the dissolved O2.
It does this by splitting O2 into two O, to combine with two HO.
This means the HO gets disappeared; it becomes H2O.

The upshot of this is that the water has less oxygen dissolved in it.
The H2O has less O2 dissolved in it.

A bit of methodical trial and error will tell you how much HO to add to how much water to get good tasting clear ice.

--

This is my hypothesis. I have not done any of this experimentation.

Somewhere there is a chemist with a headache. :)

Ice cubes found in many restaurant drinks are clear all the way through whereas home ice-makers are not. In your fridge, ice freezes from the outside in. Dissolve air gets trapped and collect toward the center.

Many commercial ice-makers freeze water in very thin layers over and over. This created two advantages: the ice is completely clear, and it actually rids the water of dissolved solids eliminating the need for ROs to be applied in most cases. The TDS is drained away as it avoids 'attaching' to the frozen part of the water. So, in a sense, it acts as a type of softener.

Take home a few clear ice cubes and a water sample from a restaurant and put a TSD meter to them, you may be surprised how different the melted ice is from the water in the glass it came from.

I am not aware of how altitude affects clarity.

"I am not aware of how altitude affects clarity"

I'm not either but observing differences between my environment with pretty clear cubes and Asolo's, altitude might have an effect.

Lower air pressure at altitude... easier for air to escape the cube during freezing?

More than that going on....there are countless providers of clear ice at sea-level, too. Surely has more to do with the process utilized than with atmospheric pressure.

Thinking not worth the effort to pursue....but still interesting.

"You can't possibly get CLEAR ice cubes from any water."

Simply wrong.

The cloudiness is caused by dissolved gas in the water.

Boil the water first and THEN cool it in the fridge and move to the freezer as soon as it hits the fridge temp (about 40F).

It will be pretty close to perfectly clear when it freezes.

It just takes more energy.

You cannot let the water cool slowly to room temperature (the air will dissolve back into the water).
You need to cool it off quickly.

If you put the boiling hot water in the freezer directly it would be even faster, but you run the chance of thawing the other freezer contents slightly.

OK...nuttiness continuing....teeing off on brickeye's advice this morning......

Boiled RO water for ten minutes; cooled for five; Pre-cooled plastic cube trays; poured 180F water into trays and immediately placed in freezer at zero; checked freezer temp after five minutes to see holding well at zero. Will report back in a few hours.

Man, I need to get a life!

This latest attempt achieved, by far, best result yet....pretty much verifying brickeyee's advice that came just before it. Cubes are crystal-clear except for the smallest pocket of "cloudiness" in the very centers -- a much smaller spot than other attempts.

Also verifying his advice, under magnification it can be seen that the tiny bubbles at the outer edges of the spot are elongated -- appearing to radiate from the center toward the edge. These tiny air pockets were clearly "frozen in-motion" as if they were trying to get out of the middle but couldn't make it. They are more elongated closer to the edge. The tiny bubbles in the middle remain spherical. This is the same appearance of the bubbles in my machine's crescent-shaped cubes.

OK, I'm done. This is too much of a hassle to bother with for a supply of "clear" ice that still tastes the same and functions exactly like my cloudy ice. Still think interesting.

"Pre-cooled plastic cube trays; poured 180F water into trays and immediately placed in freezer at zero"

You let it cool to much (unless boiling is 180F).

Higher altitude will of course lower the boiling point leaving more gas dissolved.

Try a pressure cooker.

Believe boiling point here about 207 or 208F.

In any event, too much hassle to bother with.

Or maybe get something like this portable "clear ice" maker for a few hundred bucks. One example of several available.

Nah. I can buy an awful lot bags to ice for that kind of money. Bet you it doesn't even work right with RO water anyway. Lot's of appliances don't.

Here is a link that might be useful: Clear Ice Machine.

Way back, my dad was one of the "icemen" for a small rural town with their own ice house. They froze their ice in I believe either fifty or one hundred pound blocks and it was extremely clear. Their was a hose attached to each of the rectangular molds and they pumped something through the ice as it was starting to freeze. At the time I thought it was just air, but more likely it was something else. What ever it was their ice froze clear.

Brickeye is on to something bigger than increasing the BP with the pressure cooker. They will purge the water of dissolved gasses somewhat more effectively because there will be no gas other than steam above the liquid water.

Promised myself I'd leave it alone but just couldn't........

Have been freezing 3ppmTDS RO water in plastic ice-cube trays for several days. Room-temp water poured into plastic trays and placed in freezer at zeroF. Takes about 5 Hours for thorough, hard freeze. (But I peek a lot.) Good, sort-of-clear cubes. Nicely shaped but still with that "cloudy" micro-air-bubble center. Fine. Good ice. These cubes slightly larger than ref-made crescents and their more-cubicle shape doesn't suck up to the sides of circular glasses when drinking. Intended not going further than just this superior shape. Heck with it. Then......

Once ref's dispensing bucket was filled with my manually-made RO-water cubes, got a wild hair and thought I'd complete my "experiment" using non-RO water for a couple of trays so I could compare. I filled one tray with softened water (zero grains hard) and one tray with city water straight from household supply (about 8 grains hard)....both reading about 200ppmTDS. Wanted to observe the differences, if any, although wasn't expecting much...probably increased cloudiness. I already know both of these waters taste terrible, which is why I got the RO system in the first place -- won't be using these cubes for consumption. Some interesting differences......

Both of these waters freeze entirely differently from the RO water....water-tops in the cube-trays remain level and less disturbed throughout the freezing process. Both trays appeared "more relaxed" during freezing than with the RO water. For example, the RO trays always show a few cubes with frozen spikes popping out of a few cubes, sometimes up to 1.5 inches long....sort of a little frozen-in-air breakout attempt...little ice-needles sticking up from several of the individual cubes. Every tray always has at least a couple of these with some others showing "almost-but-not-quite" eruptions. The non-RO waters didn't do that. Not a single cube. All cube-tops level and smooth. As with the RO water, quite a number of them popped free of their molds spontaneously at the end of their complete freeze. And "complete freeze" is where the differences really show up.

Having earlier and throughout appeared to be just as clear as the RO cubes, these hard-frozen cubes turned decidedly milky at the very end. Examination via 5x optivisor lenses shows different freezing pattern internally. The imprisoned air bubbles look much different and there appears to be some other opacity overall that I can't quite make out....assume mineral content, but don't really know. Placed examples of all three in clear glasses of RO water and allowed them to melt away for twenty minutes. The RO cubes were clear, smooth, and shiny except for the still-extant central opacity. The cubes from the other waters showed milkiness throughout in addition to the central opacity plus slightly "gritty" surfaces -- no observable minerals or anything, just an entirely different surface texture. Both of these bad-tasting waters made cubes that appeared and behaved exactly alike and they both made the RO water they thawed in taste bad.

OK, done. Now if I can just get this 60's tune out of my head, I'll go to bed. : )

LOL, asolo, the knack can be difficult to live with.