Planted tank with no co2??

Also, in a planted tank with no co2, how long should the lights be on during the day? And how long should they be on with co2? Thanks!

It depends on what you want to grow, the lighting intensity and depth of the tank to name a few things.. Typical would be 8hrs/day, but your setup may need more or less.

Keep in mind, glutaral products like API liquid Co2, Seachem Excel or Metricide 14 can be used for CO2 if your stocking level doesn't produce enough for your specific setup.
 
Agree with Freshy above......depends on many things.

In general, the same lights suitable for low tech would not be suitable for high tech. Effects of too high intensity on low tech tank generally can't be overcome by limiting duration. Better to set everything up for one or the other.
 
Light duration has nothing to do with CO2 or no CO2. I would shoot for 8-
 
Light duration has nothing to do with CO2 or no CO2. I would shoot for 8-
Let me expand a little on my earlier comment.

Let's say you have one T8 bulb over a low tech tank. Duration probably doesn't matter very much, and changes will have minor effect. In fact, you may require longer duration for growth. Let's say you go to twin T5NO. Duration will have more effect. Too long of light period could induce algae. Now let's put a quad T5HO with good reflectors over same tank. Duration will have a great effect. Leave that on for 12 hours and you may be able to sit there and actually watch the algae grow.

My only point is that I believe there is a relationship between light intensity and duration. Part of the three legged stool (lights,ferts,co2). Like always, only speaking from my personal experience of having such set ups for years.
 
AquariaCentral.com