My plants grow fast and to keep low nitrates is very hard. Nitrates always
stay 20-40ppm. I tried almost everything but nothing helps. I just can't
find the cause of the problem. By the way which one is it? Brush-Red or
Hair algae? What would you do in my shoes besides buying a true SAE. I
know how to balance the tank but nothing works I suspect the gravel is
bad. Algae keeps infecting my plants because of gravel. I believe, once I
start over I will destroy current algae so it won't grow back. I'm just a
little bit confused now because to start over will take me about a month to
do a cycle and cleaning everything in 70G tank. The funny thing is I tried
a few experiments by putting some plants in dark place for two weeks in a
bowl of water but algae isn't afraid of dark My lights stay up for 10
hours a day, I feed once a day, I do water change once a week about 20%,
etc. About 2 month ago I cut all my infected plants and everything was
perfect and a little later it started again.

You can start over all you want. You are still going to have algae problems.
Only when you listen to people on this newsgroup and start getting your
nutrients in balance are you going to have a tank that controls algae.

If your nitrates are not zero, then there is something else. What are the
measurements of your phosphate, iron and CO2 levels? Are you dosing potassium?
how much?

How do you think your gravel is causing algae? Gravel has nothing to do with
nutrients except in its role as a home for denitrifying bacteria.

N. Wise
http://members.aol.com/nwwise01/