OK, I checked the threads, a lot of very experienced and talented reefers have responded.
One thing I think is clear is that water changes are not helping. You are only removing water and putting in freshly made water (read: food) for this fairly nasty bloom of phyto.
Are you still running the sump? I would probably turn that off and remove all hosings/overflows. Can you run the skimmer without the sump? If so, use it, otherwise forget it. That is only making things too complex. People run tanks at 5-10 gallons now with little to no serious tech behind it. It might be wise to start removing things until the algae blooms stop.
Do you have a cannister filter or some other sort of mechanical filtration? Aside from a wet/dry, you might want to run just a fluval or eheim for a while with carbon, a nitrate sponge (the rock material, not a real sponge) and the Kent silicate/phosphate sponge media.
Have you stirred up the sand recently? Do you have a plenum?
I can understand giving up, a lot of people have gotten out of the hobby for a lot less. If you are going to give it a little longer, just start removing things as I suggested until something changes. If you were to remove everything and just run powerheads then you would just have a tank filled with saltwater. Something is awry that is causing this to happen, if you start dumbing the whole tank down a bit you might stumble across it.
Sorry if this is a repeat of what others have said, but there seem to be a LOT of messages about this (which is a pretty good thing!) and I didn't get a chance to read them all.
Good luck.