PAR vs Time

[Doug_E]

What effect would increasing brightness and reducing time on have for plants and algae?

I have a Plant 3.0 that I keep on about 12 hours a day. I have it ramp up slowly and down slowly to start/end the day. It is on at the highest brightness (40%) for about 10 hours. 

How would the plant and algae growth be affected if I were to have it on for less time (6-8 hours?) but brighter? 

Plants are:

• Jungle Val
• Dwarf Sagiterius
• Anubis's Nana
• Anubias Nana Petite
• Java fern
• Water Sprite
• Staurogyne Repens
• Monte Carlo (hoping soon)

My tank is a 40 breeder so it is only 16" tall. 

Edited April 2, 2021 by Doug_E

[Doug_E]

5 minutes ago, Streetwise said:

 

I read through that one (well, scanned much of it) and it helped get me started. 

After a few months I'm wondering if I need to adjust my lighting and curious what would happen if I increased the brightness but reduced the time. I don't think that thread has anything that directly addresses this. 

[Littlefish]

That's a good question, I've wondered myself.

[Betsy]

I'm part of the lower intensity for longer hours school...but I'll be interested to know your findings!  You could always increase your intensity and keep the same hours for a few weeks and see what happens!  

Are you running CO2?

[Jungle Fan]

It would also depend on what type of plants you have in your tank, some would do well, some would suffer. Whenever plants suffer algae gains the upper hand, someone will use the nutrients. Most folks only consider time, brightness, fertilizer dosing, and  maybe CO2, and water changes; what they forget to consider are the different color wavelengths of light (most plants prefer red and amber, algae love all but especially blue because it doesn't do much for plants), and the needs of individual plant species, as in low, high, medium light, temperatures where they thrive, or might just only exist, and of course root tabs and trace minerals.

Tweaking all of these factors is a never ending endeavor, just when you think you have figured it all out something will throw you a loop and have you puzzled, and sometimes you find out that a fish, or shrimp share your affinity for a particular plant but just in a more nutritional way.

[darkG]

I have irregular hours, I mean yeah but the tank light is irregular too, anyway I begin to notice certain plants closing up when they have had enough, especially my Rotala rotundifolia seems to signal distinctly. So keeping an eye on plants may be useful in these kinds of investigations.

Edited April 3, 2021 by darkG

[KBOzzie59]

40% seems kind of high for a 40 breeder.  My 60 is 25" tall and I'm running just under 25%.  1 hour ramp up 2 hour ramp down for a total of 8 hours.

 

edit: post submit spell check.

Edited April 3, 2021 by KBOzzie59