Chilledaz your PM inbox is full, I haven't been ignoring your question. You need to empty the inbox before anymore PM's can come in. So the answer to the question you asked is yes, you can use Eco as a single substrate. I have that as a sole substrate in several tanks.
I put an airstone into a bucket of tap water overnight and it was at 7! I plan to cycle it again since I haven't been adding ammonia since the ph trouble. Now I'm thinking of just keep the ph at 6 and just stocking fish suitable to that level!What is your tap water ph after you let a cup sit out and aerate or stir it off and on for 24 hours? Information on your tank is needed to possibly answer that question. One thing tho is a ph of 6 can cause your BB to stop working so you need to address getting your ph up to at least 6.5
What is your stock list? Usually it's add the least aggressive to most but there are exceptions to that rule so need to know what your adding.
I've decided to stock
1x dwarf gourami
8x neon tetra
6x celestial pearl danio
6x panda Cory
6x oto