From what I can see, your second 10 gal is waaay overloaded. I've bred and raised fancy guppies, trust me they can be messy, and depending on the lines used in breeding, delicate. Also, your 20 gal needs some serious reorganizing when it comes to your fish. Gouramis grow to large sizes and do not tolerate others of their own species very well (even if they are coping, I guarantee you that there is some stress in that tank). That neon tetra needs to be moved to a more peaceful tank ASAP. Trust me, gouramis are somewhat aggresive (both genders) and its only a matter of time before that tetra ends up as someone's dinner or punching bag. By the way, what type of algae eaters are you trying to add, and to what tanks?
As to your water, I won't bother going into the whole RODI and distilled water discussion. I also use tap water with conditioners (trust me I wish I could use RO
), but I also have a filter on the faucet that I use for water (I know it's not the best, but I'm sure it helps). If you are using pH up and that doesn't work, try going to a more concentrated form like a powder that you have to mix.
Remember although there are some products out there that sell for way over what they should be, generally you get what you pay for, and unfortunately in the freshwater trade there are a lot of products that are just money pits and don't actually work.
One last thing, while plastic caves and decorations are nice, try to get quite a few real live plants in there. They look good, and do a world of wonder for your tank (oxygenate water, help keep nitrates down, clear water up,etc.)
Sorry for the long post, but I hope this will at least help some with your tanks.
