Apologies if someone else picked up on this, I did read through just never seen. If your 4DKH fluid with the bromo already added is green before you put it in the DC and tank then that sounds like a faulty batch unless some thing's changed I haven't heard of! Your 4dkh should be blue when exposed to atmospheric air. Another thing worth mentioning is you seem to be breaking down and cleaning your filter too many times IMO. Nothing against keeping a clean filter but after strip down they take a couple of days to get up to their full working capacity again and loaded with good bacteria. Once a week cleaning is breaking up the filter just when it's getting going.
Patience is another main factor. When I read back your OP you say you were ready for giving up! So many people have been there myself on many occasions
It often causes you to knee jerk and try this today then that tomorrow and then something else when you read some more info from a post that may be similar to your situation or not at all.
Nothing advised to you thus far will kill that algae off by the end of the week. Everything advised so far will, if kept up regularly sway your tank back in the favour from algae to plants. The high dosing of liquid carbon will without a doubt kill the algae but until the other issues are resolved it will come back. It's a constant battle between the two even when your plants are healthy. They just sit in the tank waiting for a chance to flourish.
I would heed all the advice Clive has said, put the Koralia where it needs to be for best flow, make sure your DC fluid is ok and set the co2 so it is yellow at lights on and pretty much stays that way until lights of. Generally 2 hours before lights on and 2 before lights off. Your dosing has been cleared as ok so keep that up. Once a week change 50% of the water and blitz that algae with EC by spraying affected areas with a syringe when dosing rather than just in the tank. Importantly, do that regularly and try and keep out of the tank for while.
Some faster growing plants would also be a benefit like hygrophilia. I couldn't see a full tank shot but it looked a bit sparsely planted.