I’ve noticed that until my plants get strong rooted they can’t out compete the hair algae for nutrients. So I work at pulling the hair algae out manually and it slowly stops outgrowing the plants.
Ok so what I would do in this situation is, cover the whole tank in a blanket or something. Run an air stone in there also. Cut the lights for 3 days. Obviously feed the shrimp (the bare minimum though). Then turn on your lights. If the algae is gone or a lot of it is gone then good. Suck up the dead algae and then monitor closely. I did this to avoid diatom algae while cycling both of my tanks (when it showed up) and while I had a wispy hair algae outbreak in one of the tanks.
I never like to tell someone what to do but from personal experience 8 hours is a bit long on lights 6 hours might be a better option to reduce this hair algae. Are you dosing any fertilizer? If so you might want to lower. At this point you have so much hair algae that just doing my two recommendations might not be enough, a hydrogen peroxide dip could work I think it’s 1 or 2 ml of hydrogen peroxide per gallon and you do that in a separate bucket and just dip your plants then wash them in tap water then return to the tank. Like you said the shrimp will eat it but 7 shrimp will not be able to keep up with this algae. Anyway good luck!
f3nnies 
I’ve noticed that until my plants get strong rooted they can’t out compete the hair algae for nutrients. So I work at pulling the hair algae out manually and it slowly stops outgrowing the plants.
Ok so what I would do in this situation is, cover the whole tank in a blanket or something. Run an air stone in there also. Cut the lights for 3 days. Obviously feed the shrimp (the bare minimum though). Then turn on your lights. If the algae is gone or a lot of it is gone then good. Suck up the dead algae and then monitor closely. I did this to avoid diatom algae while cycling both of my tanks (when it showed up) and while I had a wispy hair algae outbreak in one of the tanks.
I never like to tell someone what to do but from personal experience 8 hours is a bit long on lights 6 hours might be a better option to reduce this hair algae. Are you dosing any fertilizer? If so you might want to lower. At this point you have so much hair algae that just doing my two recommendations might not be enough, a hydrogen peroxide dip could work I think it’s 1 or 2 ml of hydrogen peroxide per gallon and you do that in a separate bucket and just dip your plants then wash them in tap water then return to the tank. Like you said the shrimp will eat it but 7 shrimp will not be able to keep up with this algae. Anyway good luck!
Reduce lighting to 4-6 hours a day or block sunlight from hitting the tank. If you are using liquid fertiliser stop.