Plants depend on several things to grow.
Light, CO2, Nutrients, Temperature are the 4 big requirements of plants in order of importance with light being the most important of all.
Your plants will only grow as fast as the most limited requirement. So in your case if you have high light but no CO2 and nutrients then the plants can't grow fast because they have a limited supply of these two requirements.
Since you have lighting covered (260w is plenty) you will want to work on maintaining stable CO2 levels and stable nutrient levels. Do not overdose nutrients, rather, choose a dosing scheme like EI (estimative index) or PPS-Pro and stick with it.
Adding tons of fertilizers without high enough CO2 levels and light levels will not make plants grow faster because they will be missing CO2.
Temperature is also important, but far less important than the first three. Every 10 degrees Celsius (18 degrees F) metabolism rate doubles. So raising the temperature from 78F to 82 F will raise plant growth speed by 22.2%, it will also raise plant nutrient requirements, CO2 and light needs by about the same percent.
Do not raise the tank's temperature above 82 F because it will likely start to kill the plants. They can only handle up to about 82F without suffering damage. If you have cold water plants like anacharis they will die at this temperature.
The biggest growth rate increase you will see is going to come from adding CO2. You could see a 300% increase in plant growth if you dose enough nutrients for them with your current lighting.
All in all you can increase the speed of your plant growth by 300-400% if you get everything right. But keep in mind, the closer you are to the limits of each requirement's parameters the faster the delicate balance between the 4 requirements can change, resulting in algae.
The key is to be consistent with everything you do. Don't drop and raise lighting/CO2/nutrients/temperatures rapidly or you will get algae.
Light, CO2, Nutrients, Temperature are the 4 big requirements of plants in order of importance with light being the most important of all.
Your plants will only grow as fast as the most limited requirement. So in your case if you have high light but no CO2 and nutrients then the plants can't grow fast because they have a limited supply of these two requirements.
Since you have lighting covered (260w is plenty) you will want to work on maintaining stable CO2 levels and stable nutrient levels. Do not overdose nutrients, rather, choose a dosing scheme like EI (estimative index) or PPS-Pro and stick with it.
Adding tons of fertilizers without high enough CO2 levels and light levels will not make plants grow faster because they will be missing CO2.
Temperature is also important, but far less important than the first three. Every 10 degrees Celsius (18 degrees F) metabolism rate doubles. So raising the temperature from 78F to 82 F will raise plant growth speed by 22.2%, it will also raise plant nutrient requirements, CO2 and light needs by about the same percent.
Do not raise the tank's temperature above 82 F because it will likely start to kill the plants. They can only handle up to about 82F without suffering damage. If you have cold water plants like anacharis they will die at this temperature.
The biggest growth rate increase you will see is going to come from adding CO2. You could see a 300% increase in plant growth if you dose enough nutrients for them with your current lighting.
All in all you can increase the speed of your plant growth by 300-400% if you get everything right. But keep in mind, the closer you are to the limits of each requirement's parameters the faster the delicate balance between the 4 requirements can change, resulting in algae.
The key is to be consistent with everything you do. Don't drop and raise lighting/CO2/nutrients/temperatures rapidly or you will get algae.
