Corrosion at brass tank tee & pressure tank

[Theodore]

Hi,
Less than 3 years ago I replaced my pressure tank because it was rusting at the threaded connection where the brass tank tee is connected (which caused a slow drip leak). Pipes on either side of tank tee are 1" black plastic. My water is on the acidic side (6.7) and hard (16GPG), and I've installed an acid neutralizer and water softener downstream of the pressure tank.
Well, the "new" pressure tank has corroded AGAIN at the SAME location and is slow-dripping again.
This is frustrating and I cannot imagine this is normal/to be expected.
Is it, maybe, a galvanic corrosion issue between the brass tee and the pressure tank and, if so, should I get yet another new tank and install a stainless steel tank tee instead?
Any/all advice appreciated.
Thanks
Theodore

 

[Reach4]

1. Do you have a corrosivity number from your lab water test?
2. I think you are saying that it is the fitting near the center bottom of the tank that corrodes. What make and model is that tank?
3. Instead of a tank tee, you can run PVC or CPVC with a threaded adapter into the tank. Then tee off from there for enough ports to do the job. With plastic screwed into the tank, you know you will not have a galvanic reaction. My pressure tank just runs pvc into the tank, and does not have a tank tee as such.

 

[Sponsor]

 

[Valveman]

Use an Amtrol metal tank or get a fiberglass one like the Flex lite. Amtrol tanks are lined where the water never touches metal.

 

[Theodore]

Hi,
To answer your questions:
1. No, corrosivity was excluded from the test results.
2. Yes, it's the fitting near the center bottom that is corroding. You can see a part of the corrosion on this photo

.
The tank is a Flexcon Industries Flex2Pro Model #WWT35, manufactured in 2017.
3. I will consider doing so when I replace it.

Speaking of replacement, Flexcon has a 5year warranty on this, I believe. Any advice on how to approach a claim on this?

 

[Valveman]

Looks like the brass tank cross, not the tank. Anything that looks like brass will corrode quickly. Your government made us take the lead out of brass, and now it turns green and corrodes from too much copper like the Statue of Liberty. Lead is an important part of many metals and was never a heath issue in plumbing. But don't get me started. Use a Stainless cross or it will just happen again.

 

[Reach4]

Speaking of replacement, Flexcon has a 5year warranty on this, I believe. Any advice on how to approach a claim on this?

Flexcon warranties your tank tee against a little discoloration? I don't think so.