@ Jan: What do they call them in Louisiana?

@ Ilovetarts: Do NOT use Yellow Out, unless you REALLY know what you are doing! It does work; but you need to be very particular about how you go about it

I'll help you, but you need to post the pool chart info first, AND have a GOOD test kit, and have posted results before you even start applying the Yellow OUT. On the other hand, you can do two things now:
1. If you have any old algaecide, go ahead dump it in - it's the best way to to get rid of it, and any problems will be over before you get finished with the Yellow Out. (If you happen to have any polyquat, SAVE that, though.)
2. Vacuum and clean any physical debris out NOW. You don't want that in the pool, when you begin treating it, anyhow.

There's a 3rd thing you can do. Borax makes your pool more inhospitable to algae, AND will work well with Yellow Out. To be useful, you need to add about 60 ppm as borates. I'm calculating your pool as about 12,000 gallons (8*8*pi*3.5 depth * 7.48 gal/cft). To do your pool, you'll need about 60 lbs of 20 Mule Team borax, or 13 boxes, PLUS 4 gallons of plain 31.45% 20 degree muriatic acid (Lowes). The borax will continue to have positive effects all season.

Get that, and get the goop and leaves and etc out of the bottom, and then you can start with the rest.

If you haven't already bought the Yellow Out, you can probably save money by buying this
5LB Ammonium Chloride AF Grade @ Amazon
Just remember, the residue from using ammonia (Yellow OUT) is IRRITATING, and will take a week or so to remove!

If you use the borax first -in part, and leave your pH HIGH, then add the ammonia, followed by bleach, and then follow by polyquat once most of the algae is dead, you'll get maximum effect with minimum effort.

Using polyquat during clean up accomplishes two things: it helps kill or prevent algae, letting you run lower chlorine levels, and it is a very good clarifier, that helps you filter out any small particles that may form.(Probably available from pool stores, and possibly some big box stores -- but you MUST learn to ID it correctly. See the polyquat page for more info.)
Kem-Tek 60% polyquat @ Amazon
Nava 60% polyquat @ Amazon