Summer's effect on plants

Hi. Here in Australia it is starting to warm up, eventually summer will hit and 30 degree days will be the norm.

Before the weather gets hot (still in the mid 20's at the moment), I want to arm myself with some knowledge...

I have been really focussing on CO2 lately and can see that it is the single area that I should have spent my time on earlier on!

As the water temperature in my tank rises, I understand that the plants metabolism will start to increase; their demand for CO2 and nutrients will rise? Correct?

So, over summer I can leave the lighting alone. And I can also leave the nutrients alone as I am dosing EI anyway.

So, over Summer, all I should really have to do is increase the CO2 going into my tank? And the reason for this is simply because CO2 solubility is a lot (?) lower as the water temperature rises and the CO2 will degass more easily?

Going from say, 25 degrees to say 30 degrees celcius, should I need a dramatic increase in the CO2 bubble rate or is it really not as 'bad' as I think?

I should be able to maintain healthy lush growth in 30 degree temps shouldn't I? Discus tanks are maintained at this temperature anyway aren't they?

Scott.

 

Hi Tom and Gbark, thanks for the replies.

Is this 30-50% increase imposed purely by the plants needing more due to their higher metabolism, or does the reduce solubility of CO2 in warmer water play a large part?

At the moment my tank is around the mid-20's. Once summer hits properly, the water temperature will get up around the mid-30's. Ok, so a 10 degree change in temp can require 30-50% more CO2. At the moment I am pumping in somewhere around 10-15 bps (hard to count this fast).

As per your usual advice Tom, I guess I am just going to have to use my eyes and watch the plants as the water warms up.

If I were to make no changes to the CO2 bubble rate, I would expect that the plants would start to loose their lush green colouration (start to yellow a bit), their growth would suffer, and, would I be right in thinking that I might start to see some BBA as the CO2 level starts to wane???

I guess the best strategy would be for me to simply turn the CO2 up just a little bit each day once the plants start looking a little off-colour? Or would I be better of making a small change and waiting a week for Rubisco to adjust before touching the needle value again?

Ah yes, I knew about this one. One year it got so hot that some of my smaller, overpopulated tanks sufferred many deaths due to O2 shortage.

My large planted tank is somewhat understocked, so I should be ok.

I live in Brisbane. There are much worse parts of Oz than here, they must go through a lot of CO2 in say, Weipa. ;-)

I don't quite understand this bit Tom, but it sounds important, so I better make sure I get it. Are you saying here that, at a given temperature of water, a certain light level might be adequate, but, if the temperature of the water rises, the light level might become insufficient? I can understand completely how the CO2 level might not be enough anymore as the water temp rises (higher demand due to increased metobolic rate of plants plus lower solubility), but the lighting??

We have insulation in our roof and ceiling fans, but no air con, dedicated aquarium fans or a chiller.

Provided I can get the CO2 level high enough, and assuming I've misunderstood the bit about light above, there is no reason why the plants shouldn't do well in the warm water? i.e. if the CO2 level was fine, lighting was fine, nutrient levels fine, should the average aquarium plant do perfectly fine in very warm water (up to a point of course).

Thanks again,
Scott.

 

Hi Tom,

Thanks for the further info and the links....I have some reading to do.

After I've had a read, I may need your help to distill the information a bit.

Tell me more about your trip to Brisbane....where are you giving the talk and can anybody come along to it? What will talk specifically be about (aquarium plants?)

Scott.

 

Hi Tom,

Thanks for the info about the presentation, I would probably enjoy something like that but don't think I would have the time to attend.

Regarding the effect of temp on CO2, I had a look at the articles that you hyperlinked. I get the general idea, but a lot of the detail was a bit over my head.

I will create a brand new thread to discuss this in more detail, in simpler 'hobbyist' terms. I have a few questions.

Scott.