I'll admit: I bought an el-chepo off eBay because my bore had been dry for some time and my Grundfos Turbo pump rusted out, and I wasn't sure how much I could pump out of it.
The water isn't salty to taste but a quick search on "stainless +anaerobic corrosion" found some technical papers which were beyond me but one seemed to say that phosphorus can be bad. I doubt that we have anyone here in town more specialist than a "pop-up shop".
I'll put it together with Duralec and see how it goes.