Originally Posted by
Tizzo
http:///forum/post/2625386
If your parameters are all optimum, and as mentioned you keep your calcium around 400ppm and alk around 8 dKh, then if will take about 3 months to see spots of it on your glass and overflows.
And FWIW, I wouldn't trust any LFS with anything. Not test results, not premixed water, not RO water, advice... pretty much nothing.
Most of them use the cheapest test kits available. I tested my own LFS's water afte he told me all his params were in check. First his RO had a TDS of 100! Nitrates off the chart well over 75, and a specific gravity of 1.018... in their REEF tank!!!
If a store does use good quality test kits, then they will charge for testing cause those kits aren't cheap!
Get your own test kits. Learn how to use them. Learn what you need and how to get it.
You can always ask. My LFS has an 800$ kit they use when they're not sure of the cheaper(200$) kits results. They do charge, but only if you aren't buying something. I've had my water tested a few times, but I never had to pay for it since my tank was finishing cycling and I just wanted to see if it would be safe for a fish. It really depends on the store though.