pH- 8.5(on the new ph kit)
This is the tap water?
You will need to remove a lot of the KH to be able to lower the pH.
Here is a way to do this:
Get a gallon of RO or distilled water (grocery store or almost anywhere).
Mix it with tap water. Try 25% Tap and 75% RO. (5 gallon bucket is great, even a 1 gallon bucket will do for this. Make perhaps a quart of the mixed waters.)
Test GH, KH, pH.
If the KH is not somewhere around 60 ppm or lower then add more RO to lower it.
Next, add a handful of peat moss. Stir that around every few hours, or add an air bubbler to keep the water moving. Test after a few hours, then the next day. Keep on running this for a week and test a couple more times.
Once you have a mix that is mostly RO, the GH might be too low. Fish and plants need the calcium and magnesium, so you might need to add a small amount of GH booster to keep the GH around 30-60 ppm.
Peat moss often removes minerals from the water (but not always). It adds organic acids that these fish are accustomed to.
If this works, here is what you will need to do to keep these fish:
Prepare enough water to totally change out the tank. Remove the sand and coral substrate. Remove any limestone rocks, seashells and any other source of minerals. Use neutral rocks and driftwood. Use a water softening substrate like one of the ADA products, or Turface or similar. If you use a neutral substrate add some peat moss under it.
Add peat moss to the filter.
When you are getting ready to do a water change prepare the water a day ahead. Blend RO and tap per whatever recipe works for you, and circulate the water overnight with some peat moss. I use a knee hi nylon stocking of peat moss in a garbage can of water. The peat moss is reusable, but the treatment takes longer as the peat moss ages. You can hang an aquarium heater in the water to keep it warm. (I run hot water from the tap to get it warm initially, so the aquarium heater is not heating the whole volume, just maintaining the temperature).
Top of with pure RO water.