Hi
@Roediger, thanks for the photos.
I am guessing here by stitching what I see in all the photos together, but the primary unhealthy plant matter seems to be on the left. You have a filter output on the left (from my view) and a power head (which is likely weaker) on the right. I suspect that your nutrient/co2 delivery is not making it to the left of your tank as your primary filter output goes across to the right hand side.
Perhaps we can try a different orientation:
1) pick whichever side you can due to tubing constraints (left or right)
2) put your filter intake near the front of the tank with your output right beside it.
Kind of like:
On the left you have the orientation I am referring to - but you have bazooka inline instead of in tank diffuser.
That may help with the distribution across the tank.
It may also be a good idea to dose everything in excess right now (I am not sure how in-line your ferts are with EI currently), but until you sort this it may be worth to upp it - alternatively, you could wait and see.
This is what I would do:
Day 0 (night):
1) Massive water change, clean hard.
2) Fix flow distribution as I suggested.
3) Start your dosing regime (I would probably aim EI'ish).
Day 1 (day):
1) Run a pH profile to see what is happening + watch the tank.
2) continue ferts.
Day 2 (day):
1) Make adjustment to CO2, then every 2 hours watch the DC and increase CO2 and watch the tank.
2) Continue this process increasing BPS until you find a threshold that you feel comfortable with - some people wait for fish gasp - some people think that is immoral. In pursuit of learning, it isn't a bad idea to go to the gasp point so that you know it.
Day 3 (day - pre-lights on):
1) Watch your ph drop and watch the tank. It will drop faster than day before because you have increased injection rate.
2) Re run pH profile
3) continue Day 2 strategy until happy
4) all along dosing EI level ish.
All along, remove dead matter, clean etc.
EDIT: I think you know this but DC lime green 2 hours after lights on is a good aim (don't worry about right at lights on - this will depend on injection rate and surface agitation). And about 1 pH drop is a good starting point.
Hope that helps
.
Josh