The regulators that are for sale at Michigan Reefers
have their stock CGA-350 nipple and nut replaced with CGA-320 fittings. These are Victor high purity dual stage regulators with stainless steel diaphragms. I purchased one of the SGT500
models from this person and it is a really good one. It has a chrome plated stainless steel body with stainless steel diaphragms and it is a dual stage model too. These high purity regulators look sleeker compared to other Victor regulators. Here
is a little more information.
I don't exactly know all of the specifics concerning swapping out nipples and nuts, but I will tell you what I've read about it.
- If the regulator has stainless steel diaphragm(s), you can swap it out. Many if not all of the regulators with a CGA-350 fitting have stainless steel diaphragms.
- Someone on this forum posted some information that he found out about swapping them. The person that he asked told him that since we are only lightly using these regulators and the working pressure is low, we can swap the nipples to CGA-320 for most regulators. If our working pressure was hundreds of pounds, we couldn't do it on many regulators.
- The regulator that you decide to try this swap on should not have a low pressure gauge that measures in hundreds of pounds. Something like 0 to 30, 0 to 40, and 0 to 60 are commonly used for our aquariums. mrkookm in the Victor
thread shows how to adjust the working pressure of a Concoa regulator.
- I wouldn't use a regulator that has been used with a gas that would be harmful to the fish unless it has been properly cleaned.
I hope this helps you.