[DarkCobra]

If I recall correctly, Algae Destroyer used to contain a different active ingredient, Simazine, which worked by shutting down photosynthesis. It was just as effective at killing plants as algae.

Now Algae Destroyer appears to contain the same active ingredient as AlgaeFix, in the same amount.

Despite the change, I'm guessing they kept it as two separate products just so people could continue to buy a brand they're familiar with; only adding "Advanced" to the name to signify the reformulation.

Maybe because of its old reputation, I haven't seen any reports of using Algae Destroyer in planted tanks. If you want to make 100% sure there are no differences, I'd suggest contacting API.