I start with R/O water.
After the R/O water reacts with the substrate. I leave it alone for 3 days.
Then check the PH, And then adjust the PH with Muratic Acid ( HCL )
I purchase the HCL from Home Depot. It is in the pool supplies.
It is 20% HCL, then I dilute it to 10 %.
I use a Saline bottle to dispence it.
If you deside to use the HCL method, BE VERY CAREFUL
I also use Muratic Acid ( HCL ), to clean the substrate.
I use a 5 gal. bucket , leaving the bucket outside , and in a safe place.
After rinsing the substrate , add it to the bucket.
Add water to cover the substrate.
Put on the rubber gloves, take the gallon jug of HCL to the bucket location.
While holding your breath, open the HCL jug, add 1 quart of HCL.
The solution will bubble, Go back and check it in 30 minutes.
I use a wooden stick to stir the substrate, if it still bubbles , check back in another 30 minutes.
After the bubbling has stopped, you need to dilute any remaining HCL.
I use the garden hose, and add more water to the bucket.
Then you need a safe place to dispose of the solution.
I use my old concrete driveway, it sure helps to clean it up, and make it look new again.
Did you use or try out the diluted HCl I have sent you? Did it work? Thank you.
I have used it but has not given me the results I want. Not sure why.
Currently my water changed in the winter and after leaving the RO water sitting for a couple of days the ph goes to around 6.8. I still need to keep testing it and see.
Newjohn wrote:I also use Muratic Acid ( HCL ), to clean the substrate.
I use a 5 gal. bucket , leaving the bucket outside , and in a safe place.
After rinsing the substrate , add it to the bucket.
Add water to cover the substrate.
Put on the rubber gloves, take the gallon jug of HCL to the bucket location.
While holding your breath, open the HCL jug, add 1 quart of HCL.
The solution will bubble, Go back and check it in 30 minutes.
I use a wooden stick to stir the substrate, if it still bubbles , check back in another 30 minutes.
After the bubbling has stopped, you need to dilute any remaining HCL.
I use the garden hose, and add more water to the bucket.
Then you need a safe place to dispose of the solution.
I use my old concrete driveway, it sure helps to clean it up, and make it look new again.
John
Thanks for the advice on the substrate. I have tried the method but has not worked that good for me.
I think it all depends on the substrate that you use.
I like to use, Normal, Home Depot , Play Sand.
I sift out the very fine Sand, Using a 5gal Mess paint strainer.
It takes time, and out of a 50lb bag, you may get 5 lbs .
I like the final product, This is not for everyone.
It is very Labor intentsive.
If you deside to use this method,
Make sure to use a Dust Mask.
That is a little weird, but that is something that most other hobbyist would not mind happening to them 
Well thanks for sharing and Happy Holidays 
