genetao, lighting alone is not all that goes into the presence and absence of algae. It also depends on the substrate, ferts, plant types and plant mass. Fish can also have an affect as some poop far more than others even when the fish themselves are the same size.
And as I said, trying to use the wpg rule with smaller tanks becomes skewed.
The type of lighting and the fixture itself can also have an effect. There's a big difference when you're getting lighting from a basic NO (normal output) florescent lighting as opposed to lighting from a top of the line TEK fixture, using T5 HO bulbs (high output).
The point is that there is no single "do this" or "don't do that" answer to algae. Maintaining an algae free tank is a matter of balancing a number of components with light being just one of the pieces of the equation.
What you can count on is that there is something there that's triggering the algae. Maybe it's too much light? Maybe one tank has more nutrients that aren't being used due to either slow growing plants or too few plants? Maybe one tank is getting light from a window? What about ferts in each tank? CO2? Substrate? Filtration? Water circulation?
The best thing I can suggest is that you go back to your basics of making sure you have ample plant mass (not all slow growers), ample ferts and Carbon (CO2 or Excel) and just enough lighting for the plants to grow well without using so much lighting that it triggers algae to grow. Keep up with the water changes to ensure good water quality.
If you keep getting algae, you'll have to work on adjusting the different factors until you figure out the root cause. If reducing the lighting didn't work, then double check the water quality. Maybe one tank has a higher amount of nitrates than another.
Keep in mind while you make changes that (1) once algae is in the tank, it doesn't automatically go away even after you've corrected the root cause; you'll have to actively kill and remove the algae, and (2) give each change sufficient time to know what difference it makes in the tank before making more changes; otherwise, making multiple changes simultaneously may leave you unable to figure out which of the changes actually worked.
I wish I could be of more help, and I hope you can get the algae issue resolved soon.
And as I said, trying to use the wpg rule with smaller tanks becomes skewed.
The type of lighting and the fixture itself can also have an effect. There's a big difference when you're getting lighting from a basic NO (normal output) florescent lighting as opposed to lighting from a top of the line TEK fixture, using T5 HO bulbs (high output).
The point is that there is no single "do this" or "don't do that" answer to algae. Maintaining an algae free tank is a matter of balancing a number of components with light being just one of the pieces of the equation.
What you can count on is that there is something there that's triggering the algae. Maybe it's too much light? Maybe one tank has more nutrients that aren't being used due to either slow growing plants or too few plants? Maybe one tank is getting light from a window? What about ferts in each tank? CO2? Substrate? Filtration? Water circulation?
The best thing I can suggest is that you go back to your basics of making sure you have ample plant mass (not all slow growers), ample ferts and Carbon (CO2 or Excel) and just enough lighting for the plants to grow well without using so much lighting that it triggers algae to grow. Keep up with the water changes to ensure good water quality.
If you keep getting algae, you'll have to work on adjusting the different factors until you figure out the root cause. If reducing the lighting didn't work, then double check the water quality. Maybe one tank has a higher amount of nitrates than another.
Keep in mind while you make changes that (1) once algae is in the tank, it doesn't automatically go away even after you've corrected the root cause; you'll have to actively kill and remove the algae, and (2) give each change sufficient time to know what difference it makes in the tank before making more changes; otherwise, making multiple changes simultaneously may leave you unable to figure out which of the changes actually worked.
I wish I could be of more help, and I hope you can get the algae issue resolved soon.