Hello cable24601,
I live in the US, but I can imagine that (good) fresh produce can be that expensive that far north given the short growing seasons. Hydroponics is a great way to go. It's a little investment, especially with
lights for growing inside, but well worth it in the long run. Here's an interesting idea, keep track of all the money spent to grow the produce hydroponically, and how much less you spend on that same produce from the store. Then do a month to month evaluation on how much you are saving for an entire year.
Keep in mind that you will become much more efficient at growing them than you were in the beginning (there is always a learning curve). So you will wind up saving even more the second year (even after a few months). Then once you have calculated how much you are saving, do something special with that money, invest it in something, make improvements around the house, put it in the bank and let it grow, take a vacation etc..
It was interesting to read about your pH stabilizing problem, it makes sense though. Did the carbon filter do the trick? I haven't had that problem myself, I always use RO water in my hydro systems. I would also suggest using some kind of filtered water whenever possible. A carbon filter will take a lot of them out, but not as much as a RO system. Don't buy a RO system just for some plants, I'm just saying use the best water you can. There are so many different contaminants in tap water that can affect your
nutrient solution. And not just pH, but also the mineral element concentrations (even toxicity), as well as the ability of the plants to absorb the
nutrients in the water in the first place. A lot of problems can be traced back to water quality issues.
The nutrient manufactures assume that you are using RO water as a standard when the give directions on mixing them, that's because they cant possibility know what is in each and everyone's water supply. Most large scale hydroponic operations have the water supply tested, and a nutrient formula designed for their specific water quality (as well as plants), but for small scale backyard growers like us it's much easier to just start with filtered water.
P.S. I know what you mean by taking so long to start seedlings (I'm not real patient that way), that's why I usually just risk introducing soil born pathogens into a hydro system, and just buy already started plants. Then just gently wash off the soil before I transplant into the system. But you cant always find the plants you want to grow, and not year round in most places either, so sometimes I don't have much choice but to start
seeds.