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Re: [SPAM] [AGA-Member] pH shock - how to support recovery?

Thanks for the detailed info, it really helps. Thanks for taking the time to go look for specs, too.
If I didn't have this kind of help, my tank would be in sorry shape by now.
Thank you, all.
I was unaware that turning off completely is not expected of most regulators, as the old setup did. Took me awhile to realize the new Victor was correctly lowering the tank pressure down to 20-30 psi, and if it hadn't been, that gas would be whooshing out at 800-900 psi. So after thinking about it last night, I hooked up the regulator and downstream equipment, checked the connections with Snoop leak detector liquid, and kept an eye on it for about 4 hours. The regulator high side reads 900 psi steadily. As you might expect with solenoid kicking in and the system still in need of tweaking, low side has been varying from 13 psi or so down to zero. It's been much better than old system about not going up above 15 psi, between it and the needle valve (or metering valve, whichever is the correct name for it.). The needle valve knob feels solid and seems to have more gradation than the old setup did. On the old valve, I had either 5 psi or 20-25 psi going out, and less than an eighth of a knob rotation between, which meant it was too easy for me to zap the poor fishes' tank pH up and down.
On this new setup, the pH was about 7.8 - 7.9 before I hooked it up, and on opening it up the pH meter went right to 7.5 (wince) but I've been trying to keep it there at 7.5 steadily while I tweak. It went back up to 7.7 at one point.
Did hardness tests immediately after I had pH=7.5.
dGH=7, dKH=5, which per Chuck Gadd's CO2 calculator, means the CO2 supply is lower than I eventually want it, but I'm trying to shift it slowly.
More comments interleaved below.

S. Hieber wrote:

A couple of points that might (?)_ be helpful:

A regulator made for CO2 usually will be capable of high
side gas pressures of 2000 or even 3000 psi.

This Victor is stamped for 3000 psi on the body, and one of the websites (not sure if it was the Victor site itself, might have been Airgas) stated that it was a light-duty inert gas/ CO2 regulator.

CO2 tanks are
usually specified for around 1800 psi, or 2000 psi, or more
depending under whcih DOT regulation specification it was
certified. A CO2 tank in the USA is allowed under DOT
regulations to be filled to a specified weight (which is
actually stamped on the tank along with the Tare weight).
Contact me offline if you wnat to know how to translate
what's stamped on the tank.

The DOT specified net weight that a CO2 tank can hold
results in a tank pressure at normal room temps of about
650-850 psi.  If the gas shop overfilled your CO2 tank
enough to break a CO2 regulator, they must be ignoring the
DOT regs and your safety as well since they would probably
have to be filling the tank to more than 2000 psi. If
that's the case, consider finding another gas shop.

Certainly have been thinking about it! One of the other difficulties for me has been that they're not open late or weekends for questions. Is this common among welding supply places? Nobody live at Victor, or at Airgas, on weekends. (Yep, I tried that, before I bothered the AGA list!) Odd, since Airgas is selling all kinds of other safety equipment.

Diff regulators will be designed for diff optimum operating
low-side pressures. I have a Scott's 2-stage regulator
that's stable down to just a few PSI. But it's a very
expensive regulator (about $400 new) that I picked up used
just to try it. Some regulators have an optimum low side
range above 10 psi.

I think most of the CO2 regulators for the hobbyists are
good down to about 10 psi. I can find your model in the
Victor price list but not the specs -- but I suspect the
regulator can withstand high side operating pressures of at
least 2000 and probably 3000 psi.

Adjusting regulator outlet pressure. Unless the outlet line
is partly open then adjusting the regulator to a lower
outlet pressure will not show results on the low side
pressure gauge. The pressure can't drop until some of the
gas in the low side of the system leaves. One way to see
fast results is to adjust the regulator lower and then open
the metering valve until the regulator low side gauge stops
lowering. The same problem doesn't occur for adjsuting the
regulator higher -- in that case, more gas is forced into
the low side until the set pressure is reached.
I'm not familiar with NoShok's line of needle valves or
find any cv specs on their website, so I can't comment on
their performance. Generally, diff valves will be usefull
for diff ranges of gas flow and for aquatic gardening,
we're interested in very tiny rates of flow. The lower the
volume of gas flow for which a valve is intended, the more
likely that it will be easy to make subtle adjustments. The
others, intended for large flow rates, will change the
aquatic gardener's CO2 flow tremendously if one just barely
turns the knob at at all. That's an inconvenience and not a
fatal flaw. I prefer the expensive Swagelok B-SS4, which
allows one to make large turns of the knob for very small
changes in gas flow -- but most folks are content with
cheaper valves.

How do you find valves and couplings?? Many aquarium supply websites sell complete setups or a few random parts, but they often don't list what kind of diameter their parts are (let alone threading, as in my Milwaukee setup weirdness), so you can't tell what couplings to get. It was simpler to gamble on ordering the Nu-Shok and the solenoid from an aquarium supplier who also sold Milwaukee controllers (as I already have). Proper valve companies, I wasn't clear on the kind of cv desired, and I wasted three evenings trying to sort out solenoids... I kept getting lost among different specialties and company divisions. I was thinking about going with a Clippard metering valve, but apparently the Clippard valve part number recommendations from the Krib are out of date, no surprise.

If your regulator can't maintain a low side pressure any
lower than about 25 psi, then you will need a needle valve
that is capable of adjusting very finely when presnted with
relatively high pressure. The higher the pressure, the
smaller the valve opening the smaller the changes in valve
opening required to make small adjustments.

a few more comments below. . .

--- Heather J Gladney <hgladney@comcast.net> wrote:

A No-Shok needle valve follows the solenoid. Is this
sufficient as a metering valve?
Today I put the Victor regulator on, with no further
equipment, to see if it was working. It does bring the pressure down to
about 25-30 psi but no lower. That alarmed me enought hat I have not
tried to put the rest of the equipment on. From the regulator, the line
goes to a solenoid (which goes into a Milwaukee pH meter) then to
the No-Shok needle valve.

It had a needle valve on it. The old setup was one of
those locked-together pieces with a Milwaukee regulator to
solenoid to needle valve into bubble-counter, the sort of setup commonly
sold on aquarium websites. When the overfilled CO2 tank blew out that
regulator, and then the overflow wouldn't reseat, after many adventures,
I got the Victor. THe Milwaukee setup took some tweaking to get
the flow where I wanted it, but once I got it set up it was fine. I ust
figure it'd be nice to have a regulator that doesn't die when the
overflow valve gets hit.

The rebuild kit for your medalist regulator is listed at
$37 retail and probably is available for less. The
"overflow" is basically a spring and disk and replaceable
if it malfunctions.

Good to know, thanks! Normally I'd like to fix the old system, for backup or hand it on to somebody else who needs one.
The gas shop guys said that the old regulator (the Milwaukee) had a plastic overpressure disk instead of a rubber one, and it might not reseat once damaged. The gas shop guys sent it in to their repair guys to work on it, and when it came back to me, I found that it was okay up to a quarter-turn of the main cylinder valve. Then it started screaming. (BTW, Mike--I haven't stopped jumping when this happens. Just not quite as high a jump.) Over the next few days, I had to close the main cylinder further to quiet the overflow scream. Odd, as once you open the main cylinder it's at 900 psi, no gradation about it, as you stated earlier.
I haven't found any specs on the Milwaukee regulator or the rest of the setup. Because I don't have warranty proof enough to satisfy their statements on the website (just email confirmation from distributor) and it's five months into 6-month warranty anyway, I haven't tried calling Milwaukee itself.
I couldn't loosen any of the components, such as the regulator from the solenoid, or the bubble counter from the solenoid, with slip joint pliers. I have a vise, but I can't figure a safe way to clamp it. Anybody on list who feels like trying to repair it, I'd be happy to mail the whole setup to good home.

I'd still like a bubble counter screwed inline like that,
but apparently the Milwaukee setup uses some wierd French threading that
the gas store guys had never seen before, and it'd be amusing trying to
get adapters. The other buibble counters I've found have been the kind
you put into the flexible airline, not into the needle valve
I haven't bothered to hunt down further, as part of the
tank diffusion setup has one of those yeast-bottle bubble ladders, which
I figure will give me a rough idea a little sooner than the pH meter.

You can make a bubble counter out of pill bottle and some rigid airline tubing and some epoxy. The connect-to-airline-tubing ones work well. Bubble counters are a convenience and luxury, not necessary nor a good way to judge CO2 levels. All the less important ;if you have a pH controller and solenoid. Use pH, KH, CO2 table for judging CO2 levels.

Yes, I find Chuck Gadd's prgram with the pH-KH chart very helpful.
I'm also trying to sort out nutrient levels, but let me get the CO2 reliable, and see what that does to the hair algae.

The Milwaukee pH controller, which it
appears you are using, is very reliable.

Also good to know. I've got electrode cleaning solution coming. I have been thinking about when to order a new electrode, as this one is about 7 months old, in continuous use. I believe someone on PlantGeek board commented that the Pinpoint electrodes are good quality and compatible with the Milwaukee controller. Any advice on that would be welcome.
And thanks again for the help, very much!

If you know your
KH and desired CO2 level, you can set the Milwaukee and
count on it to maintain the pH within 0.1 unit higher and
0.1 unit lower, which is the range for it's trigger points.

Thanks very much for your help!

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