Hi.
Don't know if it will help. But I've been running a trigon 190.
Lots of great info here
https://www.ukaps.org/forum/threads/trigon-190-crypt-corner-pfk-featured.22238/
I've used the same filter nozzle and skimmer setup as Gary's. I'm using a eheim Pro 350t filter. I've taken some of the filter media out. I also don't use the white floss filter media. I've also added 2 hydro nano to the tank.
2kg Co2 via a bazooka 70mm(i think) under the filter inlet.
I did, for a while try Inline co2 via UP diffuser but not for me(long story)
Lights. .
Aquaray 600 @ 66% brightness at the front. The back is the 400 @ 10% brightness. Tile in the hood.
Order of play for the tank.
Co2 on @ 2.00pm
Lights on 4.00 (ramping up over 45min)
5.00pm both hydro nano on.
Co2 off @ 9pm
Hydro nano off @ 11pm
Lights off @ 12 (off @ 11.45. 45min ramping down)
Feed the plants via EI.
I get the 1ph drop.
Drop Checker green when lights on.
Lots of water movement on the water surface. But not enough to splash.
Think I'm around 2 to 3 bubbles per sec.
30 to 50% water change per week. But sometimes go 10 to 14 days.
Tank not perfect but I'm happy. Biggest problem for me was too much light. Tank is setup near a bay window. So I cover the tank with towels when I go to bed.
I moved the tank(yes ½full) to the hall so I could decorate the lounge. The ambient light was greatly reduced and the tank improved. I knew I had to move to led. Moving to led gave me the control that I needed.
What I've learnt. If it's going to go wrong the tank will show you quickly. But if you going in the right direction. It's takes ages to see any improvement. So, 1 change @ a time and wait a couple of weeks.
If I did the tank again I would raise the level of substrate by 6 to 8 inches. Also have the substrate higher on the back. As you know the trigon are deep tanks. So increasing the depth of substrate would help with carpet plants.
I'll post some pic later.
Hope you find the right setup.
Enjoy!