Reservoir questions! Help the water noob

[southern]

Ok so I've been scouring the UC section these past few weeks since I just built my DIY UC. Finally finished it and have tap water running through it. I'm using the 27gal tough box from home de pot with 2 5" inch pots in each lid, 2 totes per light so 4 plants per light. Now I just added the top off res to the system since everyone says thats where I should do the mixing. I am completely new to water so say I start the system at 200-250 ppm and 5.6 ph when the rooted clones are put in. What ppm should the res be and what ph? I'm taking the approach less is more with the nutes(Floranova grow/bloom) so I'm going very light my first run. Oh and the system is filled first with tap but the res is going to be filled with RO. My RO was too slow to fill all those totes. I know it just takes experience to dial in my strain (NYC diesel), but any advice will help. Trying to get on Jacks level:big_boss:
- Southern

 

[RMCG]

From the FAQ at cch2o.com:


Q What should the top off res be balanced to?

A When operated properly, top off should be balanced the same as the solution in the system. Traditionally hydro growers have been instructed to top off with ½ strength or pure water to avoid nutrient toxicity but because the UC runs best with ½ strength nutes there is less of a chance of salt build-up. Ideally the solution in the system should stay balanced even as the plants use the nutrient and water. As a rule of thumb if the nutrient EC/TDS rises as the solution is depleted you are likely running your levels too high to begin with. Conversely, if your EC/TDS drops it indicates you’ve started to low. Ultimately, as solution levels drop in the system the EC/TDS should stay stable, this is a good indicator that you’re dialed in. This EC/TDS stability will translate into improved plant health and greater pH stability to boot.

Q What if I experience drift in my nutes?

A Correct it with your top off solutions. Example: system started at 500ppm but has crept to 625ppm as the solution level has decreased. That’s a 25% increase, which can be easily offset by a top off res balanced @ 25% below the initial 500ppm. This results in a top off res balanced at 375ppm to compensate. Ideally solution strength should stay constant as the plants consume it. This is a good indicator that minerals & water are being used at equal proportions.

 

[southern]

Thanks a lot RMCG. I read all their FAQs but I guess I didn't remember reading this part.