with the limestone chips in the media, I doubt that you really want to try to chemically bring your pH down. It will likely become a very $$ battle since as soon as you bring the pH down some the limestone will dissolve a bit and bring the pH back up.
I fear this could cause you some pH bouncing which won't be good for your fish, plants, or bacteria. pH down is rather $$ too. I think you would be better off trying the peat and/or coco coir in some of the containers to see if that will help bring your pH down a little bit. It will tint your water dark though.

Or you could slowly switch most of your containers over to quartz river rock without the limestone chips until your system pH settles a little lower.

Hello! I'm in Delray Beach,FL (just starting up). I went to the big orange box and bought pea sized river gravel. It runs about $3.69 for a small bag of it and I used 4 for 2- 10 gallon containers. I started with dechlorinating city water but the pH was too high even using chemical for the chloroamine they use here. So I am visiting the golf course outside our subdivision and return with water. I figure with all the fish and ducks living there, I might get the system to cycle. We need more rain!!!!!.

Oh, I have a few golf balls in the planters. The best use of those white flying missiles! And I had a fatality with the fishless cycling. I thought that all animal life would be safe with fishless cycling but a lizard met his maker.

The best way to lower pH here is to use dry pine needles. I have
lowered the pH very well here with it. I created a pine straw bog and
the pH went from the 10's to 6.8 in a couple days.

the pH went from the 10's to 6.8 in a couple days.