RO, Coco, and ph fluctuation

[FireFarmer]

So I recently got my automated setup fully complete. Two tables each can hold up to 25 plants and currently are holding 42 on drippers. I am running a 44 gallon brute for my reservoir and am using RO water. Last few times i have mixed a reservoir my ph drops especially while the tank sits. I turn the pump on and the PH goes up to 5.8 range (aeration?) because of the pump. When pumps off it goes down to about 5.6. First few times I didn't "condition" my water and it became really cloudy after a few days and the ph would also drop. Yesterday before i made a new reservoir I conditioned my RO water and brought the ppm's up to 155 with cal mag plus and let it sit for about 20 minutes. Even before the night was out last night the ph dropped back down to 5.6 range. No cloudiness yet but I am waiting for it. After I conditioned my water (20 gallons) I added 10ml of power si and then 50 grams of v1/v2 from floraflex. Any suggestions as to why my ph drops like it does? Is it because the cal mag I used (cal mag plus) doesnt have a bicarbonate in it ( i think thats what Ive read)? Should I switch my calmag to something like calimagic that does have the calcium carbonate in it to "condition" the water? I appreciate any answers in advance. I feel like I am on the right track with switching the cal mag to something like calimagic but I just want some extra advice.

Thanks guys and gals for any answer given.

 

[FireFarmer]

Also drain to waste.

 

[Dirtbag]

Are you adding silica after your calcium and or nutrients? That's a no-no, clouding means you've got nutrients precipitating from mixing something in the wrong order.

First add the silica, let it sit 10 min or so then add your calmag (or even better - tap water to bring the ppm up) then nutrients, then if necessary ph down. FF nutes don't really need extra calcium, they have a ton already and work well on their own with RO in my experience.
I'd also recommend adding H2O2 just to be sure you aren't having bacterial issues contributing to the ph drop.

 

[Aqua Man]

In addition to @Dirtbag about silica.

Without agitation ph can drop especially if there is a biofilm on the surface of the water.

With RO you are lacking any form of alkalinity which helps stabilize the ph and the form of silicon is not a silicate that will provide alkalinity

Have a read here.

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