It has been a while since I posted -had to post an FTS last week- Sorry guys!
Many other things needed my attention, exams, Cristmas etc. Besides that the tank was a mess because of two tangs who wouldn't leave the tank

The algae problem was also making my tank look like a uncut green lawn.
-------------------------
I removed one tang, the Atlantic Blue. It was growing too fast and was more and more agressive towards my other tangs.
At first I couldn't adress the algae-problem. I was feeding normal, skimming wet, using GFO etc.
The final thing it could be was my reactor media. I tested the effluent before and it was releasing A LOT of phosphates. (even after soaking in RO/DI for several months!!)
It was dumping many phosphates in my tank, despite of the use of an GFO filter on the effluent.
I ditched the crushed coral media and changed it for Aqua Medic Hydrocarbonat. It is almost pure Calcium Carbonate. Someone on a local board tested it in the lab, and there were some metals in it (<0,1%) but no phosphates at all.
After changing the media I removed al the algae manually, and they never came back. My tank looks cleaner the ever.
Then the third thing that caused the delay... Aquascaping!! It has been (and still is) a challenge to aquascape this tank. Because of it's shallowness and the depth it is not a standard shape.
At fist I bought a lot of LiveRock to make some Islands, but all the rock ended up in the sump.

I will create another "CoralScape", just like I did in the Formosa Forest. Almost no LiveRock, and let the corals scape the tank.
The inspiration for this (and the formosa Forest) came from
these Japanese Tanks. Unfortunately I don't know the owner(s).
Because corals will make the aquascape, the tank will look very bare for the next monts. (just as the Formosa Forest)
Im still not happy about the placement of corals, and of course I will buy more Acropora. So please bare with me!
--------------------------
And now some pictures!!!! Thank you all for your patience, it won't happen again!