I'd join in but I just got rid of my gaming PC (and huge desk) to make room for my new 6 foot fish tank. 😄
This was my build:
Corsair iCUE 5000D RGB AIRFLOW ATX Gaming PC Case
Corsair iCUE RGB ELITE Fans
ASUS AMD ROG Strix X670E-A Gaming Motherboard
AMD Ryzen 9 7950x CPU
ARCTIC Liquid Freezer...
What substrate and rocks do you have in the aquarium? Many rocks used in aquariums tend to affect the water hardness. As you're trying to maintain a low pH you need to make sure any rocks (including gravels) are inert (do no affect the water).
Here's some of the substrate. Westlands Aquatic Compost and Peat.
This is the blush brown sand. The bag split so I had to dump it into bowls.
These are some pleco caves, made from slate.