I have two Salifert test kits that I just used for the first time in like 6 months. They were both stored in my utility room with all my other aquarium items. Temp stays 74. I have not tested my tank in months because everything was doing so well. I took some water to the LFS out of curiosity to test. Alk showed 6 on their Salifert and 5.6 on their ELOS. Calcium showed 420 on their Salifert and 400 on their ELOS. I come home and decide to use my kits for comparison. I measured Alk at 9.0 and Calcium at 270. I figured maybe I messed up so I did it again with pretty much the same results. I took my kits to the LFS and let him use them and he tested Alk at 6.0 and Calcium at 350. This makes me wonder if my kits are bad. I know for a fact that they were reading correctly back in September 08. Is it possible my kits are bad? What options so I have if they are bad?
Alkalinity - Salifert, exp. 07-2010, batch 0605-B
Calcium - Salifert, exp. 12-2009, batch 0412-A
Alkalinity - Salifert, exp. 07-2010, batch 0605-B
Calcium - Salifert, exp. 12-2009, batch 0412-A