I have a 500ml bottle of Nilocg Thrive that I have used only few times. Unfortunately, in my small 10 gallon tank, the NT increases nitrates so I had to switch to Seachem Excel. I would say 90-95% of the liquid is still in the bottle.
Not trying to knock your extremely generous gesture but why not just do a half or quarter dose. It will last a very long time and will work much better for your plants than adding excel which doesn’t really do much aside from control some algae growth. Just my thoughts
Please keep the discussion only related to the "free for pickup" subject. I already have the discussion related to the NT and Excel in another part of the forum after which I have decided not to use the NT.