I get thread algae in my tank which is 3.4WPG EI, so maybe threads are our inheritance. I get it if CO2 is low, or where there is minimal water movement. Keeping water movement throughout a heavily planted tank is pretty tricky. I have decided to get rid of my Ludwigia arcuata, which is in front of my filter outlet and replace it with Rotala sp. "Nanjenshan", which should be a bit less restrictive of the water flow.
The brown algae is diatoms, which I am getting in my brand new 60l. It can be associated with new set ups, but a small group of Otos will clear it up for you.
Getting back to the thread algae issue, your CO2 levels may be a bit low and becoming exhausted during the photoperiod. Maybe this is way you have a lighting siesta, to allow the CO2 to build back up again. You should be running with sufficient CO2 to see you through the photoperiod without a siesta. High light tanks have a huge nutrient uptake, accompanied by some turbo growth, which you need to allow for. A lapse in dosing of anyone one of the vital elements for your plants will immediately show in a growth of hair algae, so you need to be meticulous with your dosing. This is certainly the case in my tank.
3.4WPG and EI grows some fantastically healthy and colourful plants, but I make sure my plants have everything to excess. This way, I don`t have to give algae any worthwhile consideration.
In summary, I think you may be running a little low on CO2. Hope this is of some help.
Dave.