Bit of a background story...
My fiance and I got a new apartment, and instead of moving both our fishtanks into two different areas, we decided our three goldfish were big enough to each have their own ten gallons.
So we got a nice 29 gallon tank, set it up, let it run for two days (I realize this was a bit short, but we had to move out of our current apartment within 4 days) then tranfered our fish.
Problem is.... My 10 gallon was having algae problems. The water was completely green and I couldn't see my fish unless they were litterally pressed right up against the glass. I did water changes several times, even resorted to a 3/4 water change once, but within a day it was back to it's usual murkiness.
I figured after transfering them, I would be rid of the problem. I didn't even take any water from their original tank. I put them in bags of jugged distilled water I had sitting next to their tank for days so it would be the same temperature. I wasn't worried about them adjusting to that water, because they are so used to being introduced to new distilled water. I have faith in them.
So I transfered them over, then my fiance's fish who looks like a carp compared to my two--she's one healthy fish! She wasn't transfered with any of her original water either. I didn't even put her tank decorations in the 29 gallon because it had black algae on it that no matter how hard I scrubbed it, it would not come off.

I needed some decorations, though, and took three decorations from my tank, scrubbed them long and hard with scalding water (and my hands were pretty red to prove it!), set it up and all the fish were happy and getting along great in their new 29 gallon. They didn't seem to know what to do with all the extra space! The 2 dojo loaches loved it especially.

But it seems I made a mistake putting my original decorations in the tank. But they held so many memories of older fish I didn't want to leave them out. Some spores or something must have gotten into the deepest cracks of them.
So within just a single week, my new beautiful, crystal-clear 29 gallon tank now looks like an old murky pond.

The algae doesn't even stick to anything. It's just in the water. After a long time, I learned that it will develop a very light, easily removable film on the glass, but like I said, that's after a long time, and I only learned that from my old 10 gallon.
It's annoying, because I only see shadows from the decorations in the background with the light hitting it, and occasionaly a flash of gold or silver as either a goldfish or dojo loach zooms by. I have noticed sometimes they even swim into the glass--they can't see properly. I feel that when I turn on the tank and put food in the water I'm just feeding imaginary fish.
I know a water change won't help this from experiance. All that would do is waste time and effort, and try my patience.
I spent a lot in money and time in that 29 gallon and it's stand and just after a week it feels wasted.
I've tried looking at some algae removers, but the only ones I can find have so many warnings with them I don't feel safe putting it in with my fish. I mean, warnings like "If you touch the tablets, wash your hands with warm, soapy water and consult a physicion imediately" or even "If after putting tablet in water, do not touch the water. If you do, wash your hands with warm, soapy water and consult a physician imediately"
It had so many more warnings than any other fish treatment I had ever seen and I figured "No way, this would surely kill my fish."

It's just the water... No algae growing on the decorations or the glass. Even the rocks are new. I just don't know what I can do... This ordeal completely killed my idea of possibly getting a live plant or two--I fear something like this would happen on a regular basis then.
I don't know if there's some kind of home treatment (not including bleach), or some sort of specific product I should be looking for. I'm actually going to a much larger city on Friday, and am going to at least 2 different wonderful pet stores. I wanted some advice ahead of time so I have an idea what I should do or look for.
Before it gets to the point of developing it's own intelligence and taking over the entire apartment complex.

If you could find some, I suggest putting in some freshwater mussels. They're very efficient filter feeders. Just make sure your water source has no copper or any metals in it. Just avoid freshwater clams, especially the small ones, as they could breed in an aquarium and the larvae will act as blood parasites on the fish. Stay away from zebra mussels as well since they are an invasive species that could establish themselves in sewers from larvae-laden water you may throw down the drain during water changes

I was having the same problem with my 10 gallon tank. I use Jungle Labs "Algae No More" fizzing tabs in my tank. You just drop it in the water and it fizzes and gets rid of the algae in the water but does not hurt the fish. The package does say however to if you already have algae growing on the sides and bottom of the tank you need to scrub that off with a an algae scrubber ( it sounds like you already did that) before using the tabs. You use 1 tab per 10 gallons of water. It not only gets rid of the algae already in the water but is supposed to keep new algae from reforming . You can get it at Wally World, Petsmart ( they tend to keep it next to the algae scrubbers) and Petco. If you do not live near one of these you could order it online from www.petsmart.com or www.petco.com. I like this stuff and it does not harm the fish. Some of the alge destroyers harm or mame fish but this one does not. You can check out the product yourself as well online at www.junglelabs.com

Add a UV sterilizer to your aquarium and you'll NEVER have green water again. Plus if it's properly setup, a UV sterilizer will also help control parasites and bacteria in your aquarium water.

well, a UV unit might seem a bit of an overkill for a 29-gallon...

I don't think so, I run a 25 watt Aqua UV sterilizer on my 29 gallon tank and I never have problems with fungus, bacterial infections, parasites or algae. I have UV sterilizers on all my tanks except for a 6 gallon betta tank. Heck, I'd get a UV sterilizer for the betta tank, if I could find one small enough to be practical.

hey, maybe Nakita ought to just try a diatom filter instead... That's efficient too

I agree... A diatom filter would clear up the water. As far as that goes... Any filter that will capture particles smaller than five microns would clear the water. But neither a diatom or five micron filter will eliminate the problem. A UV sterilizer will.

well, its still up to her (and her budget) to decide which method to choose. Not to mention actual availability of the equipment

Again... I agree, It's completely up to Nakita which method she chooses to deal with the algae bloom. I've never seen freshwater mussels in the pet stores around me, and I want to offer a safer alternative than algaecides.

heehee... I think it's easier to find freshwater mussels in a wet market than in a pet store

A mussel does sound interesting, but I don't think I would want to add anymore critters to the tank (Am considering, though...). Not too sure how it and the golden apple snail would get along.
Plus, I don't think there would be any available anywhere within a minimum 3 hour driving distance of here. I have never been to the Petsmart in the larger city I am going to visit (It must be new, because I have never heard of one being there before... but am making a visit this trip!), but something tells me they would have no mussels.

The idea of having a UV sterilizer sounds wonderful, but after finding a few results and seeing the price, I nearly choked from the shock. Maybe after a little more research I could find one that is within my price range. I will keep a note on that, though. No algae AND no parasites. My fishies would surely be happy.

A diatom filter was harder to find results for, and the only ones I could find were still a wee bit out of my price range. I probably won't be able to afford anything over $50 for around another 6 months...

So I think for now I'll have to go with the tablets (that and the mussels are the only two options around my price range). At least now I know a safe brand that works!
I would have to move the snail into a smaller tank for a week or two after putting it in, though. Or would it still be harmful then?

Well, at least now I can do some more extensive research on some of the things I know to look for.
I will keep notes on all these options and see which ones will be available to me.

Thank you all very much!

Read the packaging on the tablet very carefully if you go with those. Many are not safe to use if you have snails.

I personally would recommend koi clay. It takes a day or two to really see any difference but with regular use it does wonders, with my tanks at least

If there's a Chinatown or any Asian market in your area you're likely to find mussels there. You'd basically need just a pair or a trio for a 29-gallon