It's only 1.4 wpg though it would still seem relativity low light at that to me no? Yeah dropping the photo period would probably help it already seems to have. I have a pressurized CO2 system but I'd really prefer to not use it if possible or excel for that matter. I've recently begun to dose N to 5 mg/L to see if things get any better with the cyano. I also did a P test but it read 0 not that I really trust it as I know P tests can be inaccurate.
I Think I'll see a rise in both KH and GH but I agree it could be harder. There's about 100 lbs of reef rock in the tank I actually just tested to see the Kh and it was at 7 so not great still but obviously the rock is helping the tap water.
75 gallon Tanganyika Community Planted