Howdy, yes, I think it most certainly does.
Here's some observations:
I have 8 small tanks.
I had a CO2 gas tank slowly running out. Some of the diffusers ran fine with lower pressures, others did not.
You can guess the pattern of GDA.
The tanks that had funny CO2 and the diffusers that had a bit too much back pressure at the lower tank pressure.
But the other tanks, even with scrubbing with the extact same algae pad, directly transfered to the next tank, coated with fresh live GDA, never grew in those tanks.
Now I know the other tanks had the alga, but it would not grow, even with fresh live inoculum
Water changes, substrate(ADA AS, and one tank with ADA AS + PS), dosing, lighting, temp, all very similar.
After resolving the CO2, I've never had it again in the tanks, no algae fix required.
Now why could I not keep GDA prior????????????????
I could only keep it a week or two at most.
It always died off. But I had good CO2 then.
No wonder.
Other folks kept having issues, yet I could not grow the damn stuff.
The only differences I could figure: CO2.
I know I had the same nutrients/EI dosing etc, substrates did not matter, flourite, sand, ADA AS etc, no patterning there. Hard vs soft water? Naw, I have liquid rock and had it and other tanks had super soft water also.
Adding CO2 earlier, about 1 hour to 30 minutes prior, getting it going good and juicy before the lights go on, seems to help and starts the pearling asap.
To me, this is a good idea, it gets the most O2 production out of the light energy/electric sooner and prevents most algae from what I can tell.
But, the only factor is CO2 that would cause dramatic differences in the result near as I could predict. So I added more and stablized the levels, non lethal to shrimp and fish obviously.
Now the GDS is gone not in just one single tank, but 4 tanks!!
I lowered the CO2 again, Cladophora grows better and starts to take over I noted. After a few days, the GDA also pops up.
I recently(am still) started working on Cladophora.
It takes a serious beating whenn the CO2 is optimized and added early in the day before the lights come or starts adding CO2 very sooner there after.
Most CO2 systems take a little while before they start adding CO2 to the tank when the lights come, especially diffuser stones and small tank set ups etc with lower flow rates.
That CO2 delay allows the algae a window to grow when the plants are starved for CO2.
So the question now is, how much variation and at what level will the algae grow well in the tank? GDA? Cladophora?
That is why I am being very anal and interested in very precise CO2 measurements.
You need that type of accuracy to get the resolution to say that GDA will grow if the CO2 is varying between say(just an example) 5-20ppm in the first 2 hours of the tank lighting cycle. While most plants will still grow fine for the entire day and just be slowed for that initial 2 hours, the effect is still there and allows some species of algae to grow still.
This, in effect, lulls folks into thinking that the plants are fine(and they are) and they still have algae for some unknown reason even though they measure haphazardly their CO2 levels.
Now you can certainly take the approach and add plenty 1 hour before the tank lights come on and see how that affects growth of algae and plants, few will tell you that it does not help (But they tend not to have algae issues either, now plant growth issues).
Now think about CO2 for a moment.
I make the claim that 95% of the algae related issues are due to that or else something to do with NH4(about the other 3-4%). But still, most is CO2 related.
Think about how a plant growth very fast, under high light, under non limiting nutrients, then suddenly in the start of the day, you stop adding enough CO2, and the tank is low in CO2 to start with.
How might that impact new tip growth if there is not enough Carbon skeletons to make tissue?
Then later, you gets some CO2 and start to grow again?
Some plants may have issues with that 1-3 hour lull.
Other species may be fine and able to regulate their growth without bad appearances.
Another example of CO2 related growth problems is Java fern with a mixed batch of plants. Say a
Myriophyllum matogrossense and high light. The java fern demands a lot of CO2 under high light. So does the Myrio, but the Myrio has far more surface area for the same dry weight biomass as the java fern.
So it's a lot more efficient and a better competitor for CO2.
Thuis if you run the CO2 at a slightly lower than optimal level, the expression of poor growth, blackening of the leaves, etc will be expressed 1st in the java fern, while the Myrio will grow just fine and dandy.
Now lower the CO2 a tad more. Now you will see a worsing effect on the java fern, perhaps BBA. Now look at the Myrio! It's starting to see the effects and becomes fragile and whitish, the stems start to fragment (and hopefully flow downstream and fine a better location for growth, this is like seed dispersal almost).
My point is that there are various grades/transitions of CO2 levels when we have higher lighting.
You have less flexibilty.
Mainly with CO2, as it's the lion's share of the plant's uptake and one of the most ephemeral..........
So in a low light tank, repeat the above with the Myrio abnd java fern. You will have a much harder time seeing the differences between things as you lower the CO2, the demand is for CO2 is now much less.
Thus a myth is born.
See next post for more.
Regards,
Tom Barr