Increase in Photosynthesis activity after adding tap water

[paranoid]

Hi All,

I have observed that after adding tap water to my planted tank, my plants will have significant increase in photosynthesis activity.

I wish to know what's in the tap water that my tank is lacking before I add the water?

Thanks!

[budak]

I presume you refer to evident pearling or bubbling when you say
"photosynthesis activity". Tap water probably contains many dissolved gases, including Co2 and O2. If you are already injecting Co2 and your plants are growing well, there's nothing much more you need to do. Visible bubbling/pearling doesn't mean that the plants are photosynthesing more, just that the O2 saturation in the water (after the addition of fresh tap water) is so high that the gas coalesces visibly. Do read the threads in the fert section for more information on Co2 and dosing.

[chua]

The plants photosynthsis better after weekly water change. This is because water change also provide additional elements that your plants required.