Interesting video about increased CO2 effect on plant growth

[Rumpy Pumpy]

http://www.youtube.com/watch?v=P2qVNK6zFgE


I wonder if this could be applied to algae growth by means of CO2 injection into the scrubber inflow?

[Rumpy Pumpy]

I see this has been discussed before and "Kansasnative" was going to try it. Unfortunately he hasn't updated with results (if indeed he did try it)

viewtopic.php?f=2&t=507&start=0&hilit=injection

[SantaMonica]

I just posted this on another thread:

There is a very large amount of CO2 going into the water already from all the respiration going on. Only autotrophs remove CO2. Everything else.. fish, corals, bacteria (including nitrifying and denitrifying), pods, the stuff in live rock, microbes, and all other inhabitants, put CO2 into the water.

Planted tanks, of course, are like a giant autotroph with few inhabitants. Thus, it needs CO2.

[Rumpy Pumpy]

That makes sense I suppose.


So you don't think that there would be any advantage in attempting to dissolve extra CO2 in the water feeding a scrubber?

[Ace25]

Could someone appease me and put a big fan over the top of their ATS for a week and tell everyone the results? Talking like a 10" fan, not a little computer fan. I still think adding a fan is really supercharging my scrubber. I understand screens have good and bad weeks for growth, but going on 10 days straight now with a fan over the screen and it is like clockwork, must clean the screen every 3 days because it is full. Without a fan it would be 7 days for the exact same growth. Since I just noticed this and only on my system I would be very curious to see someone else try it and see if they get similar results (of course space permitting, I understand not all scrubbers can accommodate what I am asking).

[Rumpy Pumpy]

Could someone appease me and put a big fan over the top of their ATS for a week and tell everyone the results? Talking like a 10" fan, not a little computer fan. I still think adding a fan is really supercharging my scrubber. I understand screens have good and bad weeks for growth, but going on 10 days straight now with a fan over the screen and it is like clockwork, must clean the screen every 3 days because it is full. Without a fan it would be 7 days for the exact same growth. Since I just noticed this and only on my system I would be very curious to see someone else try it and see if they get similar results (of course space permitting, I understand not all scrubbers can accommodate what I am asking).

That's interesting.

Do you think having a fan there is increasing CO2 exchange or something?


Once my new scrubber is established I'll gladly give that a try.

[Ace25]

I originally put the fan on just for added cooling because it was a hot week... but since noticing the exponential growth since adding the fan I have left it on, although at the expense of my heaters running a lot more now. So it isn't something I am going to continue doing for much longer, just on hot days when I want extra cooling so I don't need my chiller to turn on. I am just really curious if there is a correlation between the fan and added growth or is it just a fluke and odd timing on my ATS where the growth was going to speed up anyway during the time frame, so that was the reason I asked if someone else could try it for a week and see if they notice similar results.

[iggy]

Alkaline solutions are different than freshwater tanks also in that they accumulate C02.

That is why some use skimmer intakes through outdoor fresh air and others use CO2 air scrubbers as wet lime before skimmer. Both techniques work well to boost pH 0.2 to 0.4 units. My tank pH is very stable with ATS at 8.1 to 8.2. I bet fan IS providing a bit more CO2 to tank.

I will try your suggestion starting next week!! I would not dare dose CO2 on a reeftank much like vascular fresh water plants target 15 ppm CO2 using soft water in range of 30-60 Gh. Tom Barr may have attempted this on macroalgae only marine tanks if you are interested. CO2 as limiting nutrient would not entirely surprise me after running planted tanks for years.

[Green]

Could someone appease me and put a big fan over the top of their ATS for a week and tell everyone the results? Talking like a 10" fan, not a little computer fan. I still think adding a fan is really supercharging my scrubber. I understand screens have good and bad weeks for growth, but going on 10 days straight now with a fan over the screen and it is like clockwork, must clean the screen every 3 days because it is full. Without a fan it would be 7 days for the exact same growth. Since I just noticed this and only on my system I would be very curious to see someone else try it and see if they get similar results (of course space permitting, I understand not all scrubbers can accommodate what I am asking).

Interesting, I wish I can help but I don't even have a scrubber yet. Just want to add that adding a fan could be supplying both O2 and CO2 that the algae needs depends on the lighting cycle. this reminds me of BBQ ,the more air you blow the more fire you get.

[iggy]

I just added a large desk fan pointed straight down. It has no chance of falling in as it is too big.

https://picasaweb.google.com/drewyou...eat=directlink

With fan on evaporation and spray increased. Algae growth was better than normal and chiller worked less! I got 1/4" of slime off screen and more than normal on backside of unlit screen. I do not get bright green algae anymore. I'll keep fan in place for now.

If I had to guess I think the improvement seen was from cooling water a bit. Fan likely works better than running across surface of the tank. I found the feel good videos by agriculturists a bit disturbing. " what all kids learned about CO2 in grade school was right....".