Light increase without CO2

[Sims]

Hi everyone,

Would like to ask if I were to increase my lights from 38W to 72W, is it a must to pump CO2 in cause I'm not using any right now just using excel flourish.

Hope someone could help.
Thanks

[TTL]

Maybe u can try to experience by plants a small bowl of plants outside where there is sunlight, add liquid ferts as per ur doing and see what will happen. []

[David]

Hi Sims

you did not mention the depth of your tank and the total volume. The benchmark that every planted aquarists is the minimum of 3watts to 1 gallon. Bare in mind that this is only a guide as some plant requires much more. Besides wattage the next important issue is intensity. This means the ability for light to penetrate to the substrate level.

It will be good if you inject CO2, but if this is not possible at the moment, you may compansate CO2 by keeping your KH level between 8 to 10. This method may not work with all plants.

[Sims]

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Maybe u can try to experience by plants a small bowl of plants outside where there is sunlight, add liquid ferts as per ur doing and see what will happen. []
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Hi and thanks for your reply,

Do you really mean experiment or do you mean that what I am asking is not possible.
Please enlighten me.

Thanks

[Sims]

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you did not mention the depth of your tank and the total volume. The benchmark that every planted aquarists is the minimum of 3watts to 1 gallon.
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Hi thanks for your reply mine is around 22 gallons. I guess thats more than enough light.

Thanks again.

[Sims]

Hi again everyone,

I am currently setting my 36W to a 10-11 hours timer. Is there a need to reduce this timing when I increase to 72W.

Hope someone could help me.
Thanks

[Allen_1971]

Sims,

in general it is recommended to use CO2 injection. Why? because in the long run it works out to be far cheaper. Sure you could probably up your dosage of Flourish Excel to compensate, but that will mean more cost. And yes if you increase your lights, it is generally recommended that you increase your CO2... Increased lights mean more energy for photosynthesis... means more CO2 needed (this is usually the factor which most limits plant growth).

As for the method of increasing KH to compensate for low CO2, I would generally not recommend it. Yes, there are some plants which can break down bicarbonates and use them... however this process itself requires more energy... meaning more resources have to be diverted to getting C from bicarbonates... also, not every plant can do this. As I earlier mentioned, the lack of available CO2 is usually the biggest limiting factor to aquatic plant growth... so if you're going to be lacking in any nutrient, lets try and ensure its not CO2

[Allen_1971]

Sims,

when you just add new lights, you might like to reduce your timing by 1-2 hours... this is just to let your plants "get used" to the new conditions.

[Sims]

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Increased lights mean more energy for photosynthesis... means more CO2 needed (this is usually the factor which most limits plant growth).
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Thanks for your reply,

I need to ask if the increase in light will do any damage to the plants if there is not enough CO2. I am also worried about the algae problem which I don't have now when I increase the lights.

My plants are growing like crazy upwards but not spreading to the sides. thus thinking of adding more lights. However my broad leaf tied to drift wood is constantly sprouting new leaves.

Thanks again.

[kenny_G]

hi sim,

to my experience, increasing light without adding co2 will bring about the groth of algae. i used to have 80watt fl for my 3 ft planted tank and i increased the wattage to 144 watt pl. within 1 week bba covered almost everything.

the reason behind as read from article, is that increased in light will reduce co2 content in water and algae like oxgenated water.

maybe if you wan to read more of it you can get a pamphlets from dennrle from some lfs.

ken

[David]

hi allen

i dont totally agree with you about the bicarbonate issue....agreed to the point where this method may only apply to certain species of plants. Disagree that it may not be a long term solution. The limiting factor is about 'Carbon', and the agent to deliver is CO2. Why CO2? Its because CO2 readily absorbs in water, delivered in constant dosage, when compressed (via compressed cylinder), duration between filling is prolonged, and better cost efficiency.

So simply put it,CO2 injection is the easiest and simpliest way to deliver 'Carbon'.

With good lighting and high KH levels, you can get very good growth, but good knowledge on fertilisation and micro-management is needed.[]

[NinjaFly]

Hi,

I was wondering if it would help if I increase my FL tube to those extra bright FL tube instead of adding more FL tube or increasing the wattage to my tank?

[David]

hi ninjafly

it depends on what you want.

the first option of changing to brighter tubes but no increase of physical bulb - increased wattage per gallon, bigger increase in intensity, little increase in coverage.

the second option of adding more tubes by inceasing physical bulb - increased wattage per gallon, little increase in intensity, bigger increase in coverage.

[Allen_1971]

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On 1/12/2003 6:37:33 PM
I need to ask if the increase in light will do any damage to the plants if there is not enough CO2. I am also worried about the algae problem which I don't have now when I increase the lights.

My plants are growing like crazy upwards but not spreading to the sides. thus thinking of adding more lights. However my broad leaf tied to drift wood is constantly sprouting new leaves.

Thanks again.
----------------

Increasing lights will not in itself damage plants. Plants are able to protect themselves from stronglight by changing pigmentation etc.

The biggest risk is that the light increase without CO2 will result in better algae growth... which is a good reason to add CO2!

[Allen_1971]

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On 1/12/2003 10:16:11 PM

hi allen

i dont totally agree with you about the bicarbonate issue....agreed to the point where this method may only apply to certain species of plants. Disagree that it may not be a long term solution. The limiting factor is about 'Carbon', and the agent to deliver is CO2. Why CO2? Its because CO2 readily absorbs in water, delivered in constant dosage, when compressed (via compressed cylinder), duration between filling is prolonged, and better cost efficiency.

So simply put it,CO2 injection is the easiest and simpliest way to deliver 'Carbon'.

With good lighting and high KH levels, you can get very good growth, but good knowledge on fertilisation and micro-management is needed.[]
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Eh David... you making me blur liao... you "disagree" with me, but then your next few lines go on to agree with me... I'm still trying to figure out where you disagree

[vinz]

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On 1/12/2003 6:37:33 PM
Thanks for your reply,

I need to ask if the increase in light will do any damage to the plants if there is not enough CO2. I am also worried about the algae problem which I don't have now when I increase the lights.

My plants are growing like crazy upwards but not spreading to the sides. thus thinking of adding more lights. However my broad leaf tied to drift wood is constantly sprouting new leaves.

Thanks again.
----------------

The broad leaf tied to driftwood... looks something like this? That is anubias. Under bright light, it may actually slow down growth and usually accumulate algae on its leaves. Keep them shaded or in a shaded area if you increase lights.

[FC]

I have seen a very successful and nice tank without CO2.

Go to Sam Yick's shop at Pet Safari and look for the 125L Jewel tank, it is located in the former's bird shop which now rented by Sam Yick. It was the demo tank used during the last talk on planted tank with arowana.

You may consider the plant use in these tank to do the same (without CO2).

Have fun.

[bclee]

Usually tank without CO2 are low light with slower growing plants (maybe some exceptions).

As Allen and some others mentioned, increasing light without matching with increased CO2 will likely result in algae bloom.

Yes, plant can make use of HCO3-, but less readily compared to CO2.

Algae need less CO2 (as with other nutrients). The C (or other nutrients) needed for a large Echinodorus to produce 1 leaf or a bunch of stem plants to grow 0.5cm, is probably enough to feed the whole tank of BBA. That is if you compare mass of plant to equivalent mass algae. 1 leaf of a large echinodorus probably weigh a few grams. How big an area can a few gram of spot algae or BBA cover?

If you increase the light, you are driving both plants and algae to grow faster. Now you will find your plants impeded by low CO2, but on the other hand, you find algae thriving on the limited CO2 available.

BC

[FC]

Yes, I agree with that all the time.

What surprised me is that the Jewel tank is full of stem plants, though less demanding types. And the plants are living very well. The setup is so simple, with just filter and lamps like a fish only tank. See it for yourself.

[vinz]

I remember that Joey (the guy who ran the workshop) uses much less light in that tank (125L) than the usual 3W/Gal guideline. Only 2 or 3 2ft FLs if I'm not wrong. He empahsised using less light demanding plants (for this case) and to put the more light demanding plants at the brightest location.