Lighting Mis-Calculation - Co2?

[Steve H.]

As in the title I thought my lighting was at 1.3wpg, but I have come to find I am actually at 2wpg.

Is co2 necessary?

I guess I don't fully understand why co2 is necessary for high lighting set-ups.

 

[DrRob]

The old watts per gallon doesn't work so well anymore sadly. I think it was based on the old T12's and worked fairly well for the T8's. However tanks are now lots of different shapes and sizes, most importantly being of different depths, and the modern lighting chucks out more light per watt as it's now more efficient (the most extreme example at the moment being that LED's at the wattage we'd use in fluorescent tubes would be very, very bright.

So, to try to answer your question I'm afraid you get questions back. How big is your tank, especially depth, what are you trying to grow and exactly what lighting are you using?

To try to put it simply, plants use 3 main things to grow, light, CO2 and nutrients (fertlisers). The more light, the faster they'll use the others and eventually you reach the point where the plants will use all of the available CO2 and then suffer, hence adding more for high tech set ups.

 

[ian]

i'll also add that the higher light you go the less room for error you leave yourself when it comes to battling algae. As the C02 needs ramping up to a level that isn't harmful to fish. As excess light is the route cause of algae.

 

[Termato]

As in the title I thought my lighting was at 1.3wpg, but I have come to find I am actually at 2wpg.

Is co2 necessary?

I guess I don't fully understand why co2 is necessary for high lighting set-ups.

Are you using any fertilizers?

I would suggest you keep track of your plant growth. If they don't seem to be going as well as it should with that much lighting then you should absolutely get some C02. Although, if they are growing without a problem then you should not have any reason to add any.

It is very expensive to add C02, unless you want to build some crazy thing to do it. IMO just keep track of what is going on in the tank and based on what i needs, give it to it.

i'll also add that the higher light you go the less room for error you leave yourself when it comes to battling algae. As the C02 needs ramping up to a level that isn't harmful to fish. As excess light is the route cause of algae.

Great point. If you notice any algae, you can always try minimizing the duration of light.

If that doesn't work you can try floating plants like Pennywort.

 

[Steve H.]

I am starting to get algae, and that's why I am asking. I looked up the algae on "the planted tank", and the noted causes for green dust algae as low co2 and low nutrients.
I ruled out nutrients because I have soil and substrate fortified with Laterite, and I also dose with API leaf zone once a week.

The tank is a 5.5 gallon with 10 inch depth. Lighting is a 13 watt 5500k spiral flourecent.
Plants are H Difformis, Wendtii crypt, Sagittaria, and a compact Amazon sword of some sort.
All plants are doing quite well with the exception of the Sagittaria....that is really struggling. Melts, rebounds, and is melting again.

 

[Termato]

I am starting to get algae, and that's why I am asking. I looked up the algae on "the planted tank", and the noted causes for green dust algae as low co2 and low nutrients.
I ruled out nutrients because I have soil and substrate fortified with Laterite, and I also dose with API leaf zone once a week.

The tank is a 5.5 gallon with 10 inch depth. Lighting is a 13 watt 5500k spiral flourecent.
Plants are H Difformis, Wendtii crypt, Sagittaria, and a compact Amazon sword of some sort.
All plants are doing quite well with the exception of the Sagittaria....that is really struggling. Melts, rebounds, and is melting again.

How long do you leave your lights on for?

I have a 5 gallon tank that started to get algae with a 7W 6500K CFL bulb. I lowered the exposure from 12 hours a day to 9 and its doing fine now. I am still trying to see if the plants will accept this.

Try and clean the algae off of what every you have.

 

[Steve H.]

How long do you leave your lights on for?

I use a 5/2/5. 5 hours on 2 hours off, 5 hours on.

 

[Termato]

How long do you leave your lights on for?

I use a 5/2/5. 5 hours on 2 hours off, 5 hours on.

I have never heard of that. Why are you doing it that way?

Try doing it for 9 hours straight and then make sure the tank gets a full 4 - 5 hours of COMPLETE darkness.

 

[Steve H.]

There is a thread here written by George Farmer that I read, and he states this method:

"5. Use a plug-in timer to control your photoperiod. I run a siesta that in my experience helps to further prevent algae. 5 hours on, 2 off, 5 on is ideal. I have tried many combinations of photoperiods from 12 hours on down to 4 on, 4 off, 4 on and find that 5-2-5 gives an ideal balance of plant growth and algae prevention. Many aquarists do not run a siesta and experience no algae problems; this is fine and is really a matter of personal choice.
I do not fully understand the science behind the siesta helping; all I know is that is works well in my tank."


I liked the sound of this and just thought I would give it a try.

 

[SO19Firearms]

I ruled out nutrients because I have soil and substrate fortified with Laterite, and I also dose with API leaf zone once a week.

I wouldn't be so quick to.

 

[Steve H.]

I ruled out nutrients because I have soil and substrate fortified with Laterite, and I also dose with API leaf zone once a week.

I wouldn't be so quick to.

I used the wrong verbage there...I guess I mean that it is not my first suspicion due to the excellent growth and condition of the majority of my plants.

 

[Steve H.]

To try to put it simply, plants use 3 main things to grow, light, CO2 and nutrients (fertlisers). The more light, the faster they'll use the others and eventually you reach the point where the plants will use all of the available CO2 and then suffer, hence adding more for high tech set ups.

Thanks for the explanation.
What would some signs be that the plants are using all available co2? How do they differ from nutrient issues?

 

[DrRob]

I find this page useful

http/www.aquascapist.com/co2-fertilization/common-signs-of-plant-deficiencies/

However, as it says, there are lots of other signs and it will tend to vary according to the plant. My hygrophilias for instance tend to end up with leaves full of holes which then fall off.

 

[Steve H.]

Thanks Dr. Rob.

A possible solution if depleting co2 becomes an issue might be Flourish Excel?

 

[SO19Firearms]

Excel would work.
The obvious signs for CO2 are identifiable algae, holes in leaves, transparent leaves etc

The nutrient point is There's not much nutrition in Laterite - It's a clay waiting to be charged with nutrient from ferts etc I'd guess the API has no measurable Nitrate or Phosphate to do that, leaving the soil - Which depending on it's NPK will be great for a lot of plants but anything with no or stressed roots might be a bit of a problem, where as nutrients in the water column are always happy to jump through the leaves.

Another aspect (it's never easy is it) - All the above may actually be at acceptable levels...it's just not getting transported round the tank due to a lack of flow. Meaning good quality flow as opposed to millions of power heads all pointing in random directions*


IMO







* a small exaggeration, but you'd be surprised....