Does high output light need CO2?

[I_Smell_Fish]

I thought I was buying a low to moderate output LED light, but it is actually a high output light. I'll keep it if my tank doesn't require CO2 because of it. I have a 15 gallon tank and it seems like it would be nearly impossible to control the amount of CO2 in such a small tank, and I'm not sure I have the time to manage CO2. Do I have to have CO2 because I have a high output light?

Thank you in advance!
Darrien

 

[StandbySetting]

Hello

Can you give us a bit more info please? What type of lighting is it? How powerful? What are the tank dimensions?

CO2 injection is easy, keeping stable levels in a 15 gallon wouldn't be difficult st all with a decent regulator and solenoid.

 

[flchamp89]

Tank size is nearly irrelevant.

Sent from my SAMSUNG-SM-G890A using Tapatalk

 

[Byron]

More data on the lighting will help us offer suggestions. There are ways of "dimming" the light if it is not excessive to begin with, such as floating plants. I personally would not fuss with CO2 in any tank, unless you are after a high-tech aquatic garden tank. But I certainly wouldn't consider it here in so small a tank.

 

[I_Smell_Fish]

The light is a FugeRay Planted + Finnex 20" with 72 7000k daylight LEDs, 40 true 660nm reds, and 8 blue. The tank dimensions are 20" x 13" x 14".

 

[DutchMuch]

to simply answer this; no

 

[Tyler_Fishman]

Lighting does not add CO2, Infact high lighting increases oxygen levels, you will need to Dose CO2

 

[StevenF]

The light is a FugeRay Planted + Finnex 20" with 72 7000k daylight LEDs, 40 true 660nm reds, and 8 blue. The tank dimensions are 20" x 13" x 14".

Unfortunately I could not find any brightness specification for the lamp. My best guess puts the light in the medium category which may be OK.

However if I am wrong there are things you can do to reduce the light:

• Move the lamp further away.from the bottom of the tank. If the lamp is raised another 20 inches (40 inches from the bottom of the the tank you will get 1/4 of the light.
• You could put something between the light to reduce the brightness. A thin sheet of paper for translucent plastic. Or you could completely block some of the light.
• Contact the manufacture and ask if a dimmer can be attached to it. Or if they sell one.

The Only issue I know that can be caused by high light and low CO2 is a PH change. As plants consume nutrients the chemistry of the tank changes. if this is happening you can check for it by checking the PH just before the light turns on and again just before the light goes off. If the PH goes up you can solve the problem by adding CO2 or by reducing the brightness of the light. Some people use PH meters to control how much CO2 is supplied to the tank or they tie the PH meter the the light and dime the light as the PH goes up. The cheapest solution to the PH problem is to reduce the brightness of the light which slows down plant growth

 

[DutchMuch]

you could also use a hanging kit

 

[Byron]

Unfortunately I could not find any brightness specification for the lamp. My best guess puts the light in the medium category which may be OK.

However if I am wrong there are things you can do to reduce the light:

• Move the lamp further away.from the bottom of the tank. If the lamp is raised another 20 inches (40 inches from the bottom of the the tank you will get 1/4 of the light.
• You could put something between the light to reduce the brightness. A thin sheet of paper for translucent plastic. Or you could completely block some of the light.
• Contact the manufacture and ask if a dimmer can be attached to it. Or if they sell one.

The Only issue I know that can be caused by high light and low CO2 is a PH change. As plants consume nutrients the chemistry of the tank changes. if this is happening you can check for it by checking the PH just before the light turns on and again just before the light goes off. If the PH goes up you can solve the problem by adding CO2 or by reducing the brightness of the light. Some people use PH meters to control how much CO2 is supplied to the tank or they tie the PH meter the the light and dime the light as the PH goes up. The cheapest solution to the PH problem is to reduce the brightness of the light which slows down plant growth

I know nothing about this LED light, so I will accept what Steven suggests concerning the intensity. I would monitor things for a few weeks (it can take a few weeks for things with plants to become obvious) before jumping to conclusions.

I do have some comments on the CO2/light issue though. First, diurnal fluctuation in pH is perfectly normal in any planted tank. This occurs in natural waters too. Seeing a rise in pH at the end of the "day" period is therefore expected and not surprising, but it will likely not be more than a few decimal points. This is because plants are taking up the CO2 for photosynthesis; how much they do depends upon the plant species and numbers and the light intensity. During darkness the CO2 rebuilds, from respiration of fish, plants and some bacteria species, but primarily from decomposition of organics in the substrate. The pH will thus be lower in the early morning, when CO2 is at its highest. CO2 forms carbonic acid which lowers the pH. I won't go into the mineral binding aspect.

My point is, that you do not need to be rushing into adjusting the light, nor adding CO2, if you see this diurnal fluctuation because it is normal. Monitor it over several days, observe the plant's response, and take it from there. I have "moderate" light over my planted tanks, and with 8 hours of light each 24-hour period the plants are responding well without algae issues, which means the natural CO2 is sufficient for this period.

Byron.

 

[StevenF]

My point is, that you do not need to be rushing into adjusting the light, nor adding CO2, if you see this diurnal fluctuation because it is normal.

I agree that small diurnal fluctuations is normal. However they are not always small. I have seen my PH change by 2 points in one day. If you see fluctuation half that size you need to stop it. it is not good for the fish. I did it by dimming my new light.