I add some Amazonia Soil to my established 5G tank. My tank just went through the treatment of killing Spirogyra algae using API AlgaeFix. Since the tank had no live stock, I replace portion (about 1/4 area) of the Fluorite Dark substrate with Amazonia soil. I used about 1/5 of the 3L bag.
Day 1-2: Soak the Amazonia soil in a container, and replace water 2 twice a day
Day 3: Remove portion of Fluorite Dark and replace with the soil
Day 4: Do a 50% water change. Test water: Ammonia: 0.5
Day 5-7: Do nothing
Day 8: Test water: Ammonia: 0, Nitrite: 0, Nitrate: below 10. Do a 50% water change
Day 9: Test water: Same result as Day 8. Add 2 young crystal red shrimps to see if they can survive.
Some info on the water parameter:
GH: 5 (R/O water remineralized with Salty Shrimp GH+)
KH: 0-1 (I added some aquavitro carbonate, before is 0)
PH: 6.4 (before light on) to 6.8 (after 7 hrs photo-period)