Will aquarium plants grow if they are under light 24/7?
Saturday, November 12th, 2011 at
4:03 pm
I want to know if my plants will grow in light that is on all day and night? The plants are in there own tank and have dirt to grow.
and will they grow faster?
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No. Plants need a regular day/night rotation as humans do. The only thing that would grow is algae.
plants require CO2, nutrients and light to grow. Adding more light/the right kind of light can make plants grow faster, but only if there is enough of the other two requirements.
no, using weak lights and running them all day will not grow plants well.
using the proper intensity,
the right spectrum of light and
a normal day – night period is always best.
They are all right for the most part. Reaching the right amount of light, A day and night photo-period. It is also commonly excepted that CO2 and fertilizers are required.
I however have been growing every aquatic plant under the sun without anything but a light bulb. Its just much trickier..
Good question. Yes they will grow if you have 1.5 to 2 watts per gallon, although as you know, needs vary widely between plant species. But In most cases you want a substantial light and dark period. They may actually grow better with a dark period. And your fish might benefit from sleeping. And you pay a little less for electricity.
If they are drawing carbon from the soil, that does throw in an interesting variable and is a neat work around so you probably don’t need CO2 supplementation. If you had two similar planted aquariums, it would be interesting running one with the lights on all the time and giving one a dark period. Know anyone who needs a science fair project?
If we think about the millions of years plants have been developing. it would make some sense that they adapted to darkness as well as light. They have light dependent activity where light energy is captured as chemical energy and pushed into a chemical called ATP (adenosine triphosphate).
The light independent activity during the night time when the ATP is used to make glucose. That is referred to as the Calvin Cycle.
The darkness also allows the plants to do some respiration related activities and that is when they actually absorb some oxygen from the water.
I do know of a guy who ran his lights 24/7 over some water sprite for a time. In our town there is a fair amount of sodium chloride in the tap water. Water sprite, being a fern, doesn’t tolerate a lot of salt in the water.
I ran my overhead shop lights on timers for 12-16 hours (they gradually go on and off – sort of a sunrise and sunset). My water sprite didn’t do well, his thrived. We’re guessing that the extra light gave the water sprite extra energy to maintain an osmotic balance and survive the salt.
Curiously desert plants can’t leave their Stomates, the pores for air exchange in a leaf, open during the day or the plant would seriously dehydrate. So they have evolved a way to open them at night and to store CO2 until later. It is amazing how plants (at least the survivors) adapt to their environments.