I've been researching for hours trying to get all this straight. I'm trying to work out a budget dual stage CO2 setup, but I'm a bit overwhelmed by all the options. Here's my current understanding:
In the case of regulators made for aquariums, like this GLA model
, the term "regulator" is used to mean the regulator body (component that drops from tank pressure to working pressure), solenoid, needle valve, and bubble counter. If you buy an aquarium regulator, you're good to go - all you need is hoses and a diffuser/reactor.
Strictly speaking though, the regulator is just the regulator body (component that drops from tank pressure to working pressure), although it often also includes gauges to show tank and/or working pressure. Industrial regulators, like this one
, use this terminology.
If you buy an industrial regulator, you need to also buy the solenoid, needle valve, and bubble counter, along with some various fittings. All these components except the bubble counter can be found as a "post-body kit"
, or everything can be bought separately. People talk about "building" regulators all the time, but making a DIY regulator is really just a factor of screwing all these components together. You're not actually buying a regulator housing, springs, diaphragms, etc., and building the regulator itself (regulator body?).
Am I correct so far, or do I have that wrong?
The first option is to buy a pre-assembled aquarium regulator. This is most expensive, but easiest. It can be cheap as $150 for this very questionable dual-stage model
, but more realistically you're looking at about $500 like for the previously-linked GLA model
Alternatively, as @jeffkrol
suggested to me in another thread, you can buy a nice, new, dual-stage regulator for $200
, add in $90 for a post-body kit
, $10 for a CGA-320 nut and nipple
(if reg isn't already this thread), and probably $10 more for a bubble counter. For just over $300, you have a DIY regulator that should be superior to GLA's $500 unit. (?)
Next, you can do the above but with a used regulator. There are so many different models I don't even know where to start, but I'm reading you can find them for $50-$100 on fleabay. That brings you in at $150-$200 for the whole setup, but finding a good used regulator can be tricky.
I found this extremely-helpful post which gives some guidance to finding a used regulator. I've also read to beware of regs with gauges that don't read zero when disconnected, as this indicates damage.
It's really hard to be specific about what models will work, and what won't. Generally, you want a max outlet puressure in the 45-100 range (which is complicated by the fact that stock LP gauges will show a 50-100% higher range than the max pressure). Looking for a gauge that reads 60-200 is usually safe, assuming the gauge hasn't been replaced. The inlet nipple and nut can be replaced, and are generally 1/4" NPT, though certain older models use 1/2-27 threads, not a big deal, you can find them.
VTS 250/450 (200 and 400 are very old models)
212/312/315/332/412/432, followed by 2 or 3 as the next number (that's the outlet pressure digit)
3800 (old, and I've had bad luck with these SS models)
55850 (VWR, but looks to be identical to 9296 + handle)
Those are some more common ones. There are lots of others. Further complicating matters is that retail companies often rebrand manufacturers' products, putting their sticker on the handle. Even further complicating matters is that sometimes these rebranding companies change the model numbers.
Harris/Fisher/Smith/Scott/Matheson is the same manufacturer.
So is Concoa/Praxair.
And the others all have aliases as well.
Anyway, that should give you enough choices to pick something workable and cheap. No need to spend more than $100 shipped.
Bump: One other thing - the VTS450 and 3104C are really big. They work fine, but they're just massive.
Another thing - most older Mathesons, and the Victor VTS's are an odd, bulbous shape. The rest are longer and symmetrical.
Lastly, you could have someone build you a DIY regulator. I have no idea where that comes in cost-wise, and I'm guessing that's typically done to achieve a fully-loaded, ultra-premium regulator, not a budget model. I read that some members of the forum sell DIY regs, and I specifically saw a recommendation for @Joshism
My BoM has me way over budget on my upcoming build, so I'd like to keep it under $200. I'm leaning toward the DIY, used regulator option - I feel like going with a quality, used dual-stage is a pretty reasonable compromise between a crappy single-stage and a fancy new dual-stage.
Is my understanding of all this right? I'd love to hear your corrections and suggestions.