Im not actually aware of any algae removing products that remove brown algae/ diatoms.
Diatoms are common in newly established tanks and they feed on nutrients in the water. Generally in new tanks this is silicates from the surface of the glass and substrate. When these silicates get used up diatoms usually clear up on their own after a couple of months. I notice your tank is acrylic though.
If they dont clear up it could be a sign of silicates in your water or high nitrate which is something else diatoms feed off.
I can see some diatoms on the side of the tank, which should be easy enough to manually wipe off then syphon out with a water change. I dont know if its a photography effect due to a blue background, but the tank looks very blue so its difficult to see if its also effecting your aquascape.
Diatoms also thrive in low light, particularly low light with a lot of blue in it. So turning up light and increasing white light can help. This promotes green algae which outcompetes diatoms for nutrients.
Personally i would just manually clean things up for now and see what happens over the next couple of months.