algae on the glass below gravel line

[TomFromStLouis]

I scrape algae off the glass weekly but try not to disturb the gravel and groundcover plants. It has allowed a significant crop of bright green algae to cover almost the entire front of the tank at the gravel level and below.

The algae does not occur on the sides of the tank near the back where taller plants keep the substrate somewhat shaded, so I have brilliantly concluded that the algae grows where the bright light shines on and through the gravel and no scraping or algae eating can happen. It is a heavily planted tank with 3wpg managed by a relatively thick headed fishkeeper who is just now getting fert doses down. All of this is no particular problem - I will scrape it and try to suck it up so it does not just float around.

My question is this: do you have this problem too? I am aiming this at high light tank keepers. Is this somehting I should not be having if my ferts were just right?

[kveeti]

I have a 4 inch strip of the same thing where the setting sun angles in the basement window for an hour every evening. My tank isn't heavily planted, but it is easy enough to stick a credit card almost straight down and pull the algae up so it can be vacuumed away.

edit... ok it would help if I could read. Sorry, I'm not really answering your question. But, yes, this only occurs where the sun hits, that one spot, so I guess it might be due to high light.

[superjohnny]

I like the credit card idea. If I were doing it I'd do it during a water change and with my free hand use the vacuum to suck up the algae as it comes off.

[wetmanNY]

RTR had an excellent post apropos this phenomenon, which he allowed me to quote at http://www.skepticalaquarist.com/docs/nutrient/sulfint.shtml Scroll down to the section "Photosynthesizing sulfur bacteria."

[TomFromStLouis]

I am already using a credit card for algae scraping and will dig in a little more next time. And leave it to He Who Is Wet and his sidekick to explain exactly what is going on. ;)

[wetmanNY]

I've learned more about the chemistry of fishtanks from Robt. T. Ricketts than from any single other person in my lifetime.

...but he knows that already...