aqua_chem
Aquarium Advice Addict
Hello Aces...
You need to get some plants into the tank that will use up the nutrients. They need to be fast growing, those use the most food. Get some kinds of Hygrophila, Water sprite, Anacharis and some the "wort plants", like Horn and Penny.
If you're not already, you need to be doing 50 percent water changes every week.
This is all you need to do and the algae will be gone.
One last thing. Never, ever use chemicals to control algae, especially ones that contain "Gluteraldehyde".
B
Are you kidding me? Gluteraldehyde is Excel, one of, if not the the most widely used chemicals in planted tanks. Its fish safe, plant fantastic, and invert safe if used within reason. I don't know if I would use it in a non-planted tank though, but I'm sure it wouldn't hurt. You can even double or triple does the stuff for a short time. Dunno if I would do that with inverts though.
What you were describing is either Green Spot Algae or Green Dust Algae, which are common occurances in planted tanks.
You don't 'need' to be doing 50% PWC unless you're highly stocked or are doing something that requires it (meds, EI ferts). Regular, 20-30% WCs depending on stocking is all you need. That being said, regular large water changes are helpful. In planted tanks, GSA is usually caused by low phosphate levels in planted tanks. I'm not sure about unplanted tanks though, but PWCs probably wont help this particular cause.
Marimo balls are large algae balls that some fish stores sell. They're pretty cool really. They are, however, one of the few things that Excel will flat out kill.
What kind of lights (T5, T8, PC, CFL, etc) do you have and how much wattage, and how long do you leave on the lights? And yes, using a credit card will usually work to remove the junk. Out of curiosity, why do you strip down your tank when you clean it?