Blue Spectrum Question

cupofjoel

Fish Crazy
Joined
Jun 17, 2019
Messages
230
Reaction score
85
I have a 48 inch fluval plant 3.0 led light. I have the blue spectrum at around 5% and so far my java ferns, anubias, and tiger lily are doing well. My question is, should I raise the blue spectrum higher? I know it's part of the spectrum that plants need, but I'm afraid of algae growth taking over.

Also, my guppy grass is not doing well. Could it be that it needs more blue light?

thanks.
 

JuiceBox52

Fish Gatherer
Joined
Oct 9, 2019
Messages
8,083
Reaction score
5,398
Location
Monroe Washington
I could be totally wrong, but I think guppy grass is actually a marsh plant that dosen't do well submerged. That could be why its not doing well
 

Colin_T

Member
Joined
Jan 26, 2008
Messages
20,849
Reaction score
5,390
Location
Perth, WA
You want equal amounts of red and blue light and if possible, a bit of green light.

If you have true aquatic plants that are struggling, you might need more light. You can have lights on for up to 16 hours a day, or add another light unit.
 
OP
cupofjoel

cupofjoel

Fish Crazy
Joined
Jun 17, 2019
Messages
230
Reaction score
85
You want equal amounts of red and blue light and if possible, a bit of green light.

If you have true aquatic plants that are struggling, you might need more light. You can have lights on for up to 16 hours a day, or add another light unit.
I am worried about algae if I up the light duration. Right now the amount of algae is minimal. I had to fight algae when I first started and it almost made me abandon the hobby. Right now only the guppy grass is struggling so I'm afraid I might get issues with the java fern and anubias if I up the blue light and light duration. I am at 5% blue, 45% red, and the light is on 75% intensity for around 8 hours.
 

Byron

Member
Joined
Feb 25, 2009
Messages
13,354
Reaction score
4,308
Location
CA
Red and blue are essential for photosynthesis, and red is the more important. Green added in does improve plant growth. Intensity itself or duration willnot make up for deficiencies in the spectrum, and vice versa.

Too much blue light can indeed cause problem algae. So can too much intensity, or not enough. Or too long a duration. The balance is key.
 
OP
cupofjoel

cupofjoel

Fish Crazy
Joined
Jun 17, 2019
Messages
230
Reaction score
85
Right, balance IS key, which is why I'm hesitant about raising the blue light anything over 5%, but I will try and see if the guppy grass responds well to the added blue. I'll have to keep an eye on my tank to see if I need to reduce it. Thanks @Byron
 
Top