I wouldn't worry about the chlorine in the tap water as its a good thing in hydro so long as bene's aren't being used. You've got a good start with the RO water so just make sure your supplementing calmag @ 100-150 ppm.
Personally I wouldn't remove any plant from a system unless its got root rot or is dead. I excel at fucking plants up yet they can bounce back quite fast in hydro. Since all the roots are white I'd say your fine, but you should know what temp your water is getting to. That being said, it would be a good idea to be using a sterilizer to prevent any bacteria growth and have a train wreck half way through flower. Quite a few of us are running the DIY UC Roots and its awesome. The recipe is on here.
Document your ph, ppms, and water level each day. You'll need to know those 3 things in order to interpret whats going on in the system, and when to feed more/less, etc.. There's also an awesome troubleshooting chart on here once you have that info that you can reference if/when you hit the "fml" point(s) in your grow. Lastly the data will show how long your staying in certain pH ranges. I personally set my systems @ 5.6 and within 48 - 72 hours they are at 6.1. I let them ride there a day and then reset back to 5.6. I prefer a drift over static pH values. Even if i hit the balance point of water/nutrient consumption and the pH stabilizes, I won't let it sit in one place for too long.
Best of luck homie
-itt