Ok, let's go through this slowly.

First off, stop listening to your neighbor. Rain water has no metals in it (where would the metals come from??). Rain water is actually a good thing in your case because it is pure water and if you let it fill your pool (while removing old water) then you can naturally reduce your metal levels. But for now, forget about metals as your water quality is more important at the moment.

@FBU is correct, your pH is waaaaaaay too low. Borax is one way to raise it but you have very low TA so, if you can find it, you can use washing soda (sodium carbonate....NOT BAKING SODA which is sodium bicarbonate). Pure sodium carbonate is not easy to find in the stores, but sometimes you get lucky. Pool stores sell it but at a major price markup. Borax (20 Mule Team) will raise pH without raising alkalinity but you shouldn't have more than 50ppm of borates in your water and I don't want you to create one problem trying fix another.

@FBU is also right in that I don't understand your chlorine numbers. I need to know free chlorine (FC) and combined chloramines (CC). Please retest those and report. If your CC's are high then your water is definitely NOT OK. You can have clear water and high CCs which is typically indicative of a nascent algae bloom.

I see you have an SWG. How old is it? The Cu you have in your water could be coming from old or damaged plates in the SWG. With your pH so low, you could have easily damaged the coating on the SWG plates and exposed the Cu metal underneath. But for right now, you are not going to run the SWG. You should do all of your chlorination manually using liquid chlorine (bleach) until we get your pool water under control.

How confident are you with that CYA test? CYA of 0 is unusual but not unheard of in winterized pools. Certain types of Bacteria and algae can consume CYA during the winter and produce ammonia. Sometimes a 0 reading is caused by operator error during the test OR because your other water values are so far off that the CYA test is not accurate (especially with your pH being so acidic).

Which leads me to another question - how did you get those pH values? The K-2006 kit uses phenol red indicator which doesn't show color changes below 6.8 and certain can't read down to 5.4.

Please respond with the following water parameters using the K-2006 :

FC
CC
TA
pH
CYA
CH (this one is not very important to get right at the moment).

DO NOT ADD ANY CYA UNTIL YOU GET A FULL SET OF RESULTS. If your CYA test is off and you do have CYA in the water, you do not want to overshoot as the only way to lower CYA is by draining.