Every time I see someone with an algal problem everyone has these two answers:
1. Your tank is not in balance you need to get it in check.
2. Chemicals aren't the answer spot treat but maintain the "balance" first.
Now I'm no jedi but I'm just curious...why aren't chemicals the answer in combating algae. A systemic treatment of chemicals could easily eliminate the algae problems and as long as no other filamentous algae are introduced to the tank via fish or plants (easily preventable) then the problem is done. And it's done for good. As they say with treating for ich: An ounce of prevention is a pound of cure.
I think one of the reasons we shun chemicals is because well...we call them chemicals. We call fertilizers fertilizers since they fertilize! Ohhh that sounds green and nice. But in essence they are chemicals. And they are chemicals that are actually potentially hazardous to us people. Why don't we call algae treating chemicals something like "phytocontrol" or something?
But aside from that I also believe it's because of the whole mentality of "this is slice of nature. It is a nature aquarium." But when you look at botanical gardens on land when you have a problem with scale? You spray it. You have a problem with aphids? You spray it. Mites? spray. Termites? Spray. Ants? Spray. Beetles? Spray. We don't seem to care on land as much as we do with our aquariums. Certainly we do have fish in there but there are chemicals specifically designed to be fish safe. Surely it shouldn't be dosed as it would a fertilizer but "phytocontrol" agents could easily become a part of a monthly regimen after the first systemic dose (which can be done with the fish removed) that's not only easy on fish but would be able to keep algae down. I like making life easier and sometimes the "balance" isn't as easy as killing your dad.
They do not grow plants...which is why folks have bad algae issues, they are not focusing or have a simplistic view about what grows plants.
It's ironically pretty simple, name one person who got into planted tanks to learn the algicidal methods available?
The goal is to grow a nice garden, not learn how to kill algae.