You haven't given much info about your tank, lights etc. Without having all of the specs I would say that because of the T5HO lighting you will need a comprehensive dosing regime that includes macro, micro nutrients and carbon (CO2).
Ten hours is too long for what is probably high light on a brand new tank. Cut light back to 6 hours until algae is under control and the tank starts to mature. Then you can bump up the photoperiod slowly while looking for any additional algae problems. Raising the fixture would help too or putting some window screen between the lights and tank to cut the intensity.
Hard to ID the algae type without a photo, may be rhizoclonium if it is suspended within the hairgrass as opposed to attached to it.
Ten hours is too long for what is probably high light on a brand new tank. Cut light back to 6 hours until algae is under control and the tank starts to mature. Then you can bump up the photoperiod slowly while looking for any additional algae problems. Raising the fixture would help too or putting some window screen between the lights and tank to cut the intensity.
Hard to ID the algae type without a photo, may be rhizoclonium if it is suspended within the hairgrass as opposed to attached to it.
