FWIW the only fresh alk kits I've ever had trouble with are Salifert. I've seen Nutrafin kits get wonky after 6 months or so but fresh ones are usually pretty good and the replacement solution is only $3. Never used Elos much, seems to me like it's the same indicator as the Nutrafin at a different concentration.
You'll never know what is up for sure unless you have a standard to check against. If you have a scale that measures grams you can do this:
1L RO/DI + 148g dry sodium carbonate should give you a 140ppm | 2.8 meq/L | 7.8dkh solution.
Get sodium carbonate (washing soda) by picking up some Aquarius pH+ pool stuff at Crappy Tire.
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