Need some water advise

Hey guys, I have a small problem and would like to get your input.

Currently I am in a hydro set-up and growing about 2-4 plants in a 6 Gallon Reservoir.
The water that comes out of my tap is no good for growing, which is quite bothersome.
It comes out 110PPM and a pH of 6.8 the problem that I have is that when I add nutrients to my reservoir, I start to grow algae and all sort of other ish.
If I use store bought RO water, I have none of these problems. For this current grow I have been purchasing water at my local walmart, which was fine for the 6 gallon rez.

Now that I am stepping my game up, I am growing 4-8 plants. I will use the 6 gallon reservoir as my main res and connect 4 5G buckets to it. That would be 26 Gallons (roughly) that it would take to fill up my stuff. That's a little too much money to buy it a store weekly or even bi-weekly.

Now I have considered getting a RO filter system, but the room that I grow in is 3 rooms away from the nearest faucet. Also the water in my kitchen comes out at a very low psi, which would make getting a RO system to work properly a pain in the ass.

Does anybody have any suggestions of other possible options for me?
This water situation is annoying me, wish I could just use my tap water...

I just use tap water in my res, ph down it, nute it, keep it cool, no light, and add some 30% peroxide every 3 weeks or so (0.5ml / litre).
Never had algae yet (knock on wood), good luck!

Trust me, I have tried! Wrapped the entire reservoir in white duct tape, then over that I used reflective tape. Covered all of the pots, holes, and lines with reflective tape as well. I used 30% peroxide for 2 weeks, comes back every morning, temps at 65F. It has been a nightmare with tap water...

Add some neem oil in your res. unless ur usingbeneficial fungi. Neem should solve your algae prob along with light proofing your containers.

Regular tap is fine to use. Use RO for seedlings and clones

Another thought..you can run a regular tap filter with that uv anti bacterial light.

I have been using hygrozymes as beneficials. Would that cause problems with neem oil?

get an ro system.... best thing you can do for your plants.. you could always hook it up on the back yard, or run garden hose into room... fill up 5 gallon buckets and dump them in until your full... if you do go this route, you will need to make sure your nuets has enough calcium and magnesium , i have to use cal-mag to supplement these . i know when i did grow hydro i used alot of cal -mag ...

and perhaps buy a black res container?

Maybe I need to go take a look outside and see if there actually is a faucet out there. I live in an apartment so the odds of that are pretty slim. I use RO water currently, just store bought. I have bought cal-mag just in case, with GH 3-part series I haven't had any problems. I am about 2 weeks away from harvest and expecting about 5 ounces when all is done. Also the container I use is black.

About 5 years ago, my town had a serious salmonella outbreak. As a result the city added certain chemicals into our tap water to prevent it from ever happening again. Maybe that is the reason why I have such an impossible time trying to grow with unfiltered tap water.

It's just so frustrating...

TL;DR - I can't use my tap water to grow because of it's chemicals.

You can run a bubbler in your reserve water bucket and get rid of the chlorine beforeyou use it. If its just Cl in your water.

Neem will kill beneficial enzymes, microherds etc.