I would be furious as well, but agree with that the best course of action is to add a support and call it a day. My tank was built by AGE and it came with a chip in the corner of the acrylic eurobrace. I got nowhere with my request for a fix and ultimately decided to suck it up and accept the tank as is. (And I am a litigator so suing would not have cost much other than the time and bother of going through it, but its just sooo much time and bother and would have delayed my build for at least a year win or lose). 4 years later, it is solid so their assurances that the defect would not affect performance has so far proved correct. Other than that though, I am happy with the build quality and particularly like the PVC bottom -- its bulletproof and allowed me to drill 6 holes for my closed loop without any concerns of failure. I had my contractor build a wood stand so I did not have to deal with AGE's metal stand.
One question about your situation (lawyer, not engineer here). How is it that the stand deflects more than the tank? Doesn't the weight of the tank and the deflection of the bottom panel cause the cross-bar of stand to deflect? If so the stand wouldn't deflect more than the tank. (I must be missing some concept here.)
And whatever the answer to that question, if the tank is not deflecting, does that mean the bottom panel as constructed is strong enough to hold the water perfect support?
I'll be PM'ing you shortly.
Interesting (though not surprising to me at this juncture) that you too had a poor customer experience with A.G.E!
As for my situation, I don't make a lot of money working for NASA. In fact, i started at the same salary as my friends did who are living in cheaper-cost-of-living areas on the east coast. It took me a long time to save up for this tank and i don't have the money to purchase another one. I think i have a reasonably good case based on what i have said before about implied warranty of merchantability and implied warranty of fitness. It is going to be very expensive to fix this and even more expensive if it fails fully. Just renting the jacks to lift the horizontal beams back to undeflected is going to be expensive, not to mention a welder to weld in place while this thing hangs over them.
As for your other questions, read my post #355. I must have been typing it when you responded.
Another reason why the top beam of the stand is gapping so much is because the vertical legs are also bending. They are actually in compressive failure based on my calculations. This actually makes the stand much weaker since the first bending mode of the legs has already begun. Its even scarier that you can SEE them being bent, and at least once a day i can hear the tank releasing stress with an audible "tick" "tick".
The steal is a different sizing then used on your stand. If that steal was used you might not have the sag. I say might not.
This is likely accurate. I can't say definitively because i have not run the analysis but based on my intuition of the present situation, deflection would be significantly decreased and strength would be significantly increased.