How many gallons is your tank? I can't really make any powerhead recommendations, honestly. Each tank is different and requires different flow patterns. It's one of those things that I kinda have to do in person. Without really knowing just how big your tank is, it's hard to really recommend anything at all.
I have an expensive fish and a cheap fix. The expensive fix is the absolute best - and can be used for years and years and keeps its value... which would be a Vortech MP10 powerhead. It's about $260. It creates waves, turbulent currents and is programmable. It has a nutrient export mode to kick up detritus before a water change. Nifty little gadget, but a gadget none the less.
The cheap fix is actually replacing the loc line that you JUST purchased with a "Hydra Aquatics Nano Vortex Flow Spinner" which is about $13. It creates random flow in the tank and it doesn't use any more electricity to operate. There is one other piece of equipment that I suggest using in conjunction with the spinner, is a maxi jet 1200 powerhead (~$20) with a hydor oscillator or what they are calling a "hydor Flo Rotating Water Deflector" (~$11) these days. Placement of the powerhead depends on where your dead spots are in the tank... which is pretty much everything in the front of the tank.
What carbon does is it absorbs toxins and chemicals, it absorbs yellow tint of the water caused by the algae (Which you will need for the following paragraph), It will also absorb some dissolved organic materials that cause algae outbreaks.
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IF you want a quick fix, which I do not advocate immensely,... take all of your rock out --- hair algae and all --- clean the surfaces of the tank on the inside and get rid of as much algae as possible. Keep the rock wet. Put the rock in a bucket and pour hydrogen peroxide over the top of them... making sure you get it on all of the algae. Then put it back in the tank and arrange the rock in a manner that will give you better flow patterns. The algae will turn white and die in a couple of days. Run carbon. Do a water change then and leave the lights off for a few more days. you can feed your fish too, just kinda cut back on it a bit.
If you don't want the hair algae to return, invest in a powerhead and the attachment, get yourself an RO/DI unit and if you have the extra money, run a little GFO and carbon in a two little fishies phosphate reactor.