Sugar as fertiliser

[limsteel]

Come to think of it, I agree with what you stated. I think I lost my way abit... I should focus on growing plants rather than killing algae.

[Plantbrain]

Most folks should

No algaicide will grow plants better really, Excel, copper to some degree but it's selective with some plant species(same for Excel), that's about it.

Regards,
Tom Barr

www.BarrReport.com

[MatthewS]

Maybe this is like the Cold Fusion project of the aquatic quotient world. Everyone said Cold Fusion was impossible and there were sound Physics laws indicating why. But two American Chemists got together over a couple of Jack Daniels, scribbled some things on a paper napkin, did some rough experiments and presto - cold fusion madness! It later turned out that it was impossible. Lesson: Jack Daniels is inspirational and the Muse of many, but when mixed with science makes for a potent cocktail

Tom is probably right. Still, you've come this far with your sugar fertilizer. I'm kind of interested to hear what happens when you reintroduce sugar into the tank. Some CO2 is of course liberated from the Sugar by bacteria metabolism in the same way fish food, plant waste and amonia get digested and respired. After all, what do we put in our DIY CO2 generators? Your's is a radical cold fusion like quest - get rid of the DIY CO2 injection and just throw the sugar in the tank! Why not? Bwuahahahaah !!!

The question is how much Co2 gets produced? Any science guys out there who can do the balanced equation and figure out how much Co2 is released from a gram of sugar assuming aeorobic metabolism? Then we could get out our Jack Daniels and scribble on our paper napkins and figure out how much you'd need to put in to boost CO2 by x PPM in a tank of a given size. We'd need to simplify - forget about gas exchange with the air and the fact that some of that carbon gets sequestered by bacteria growth.
Your quest has made for an interesting and entertaining thread. I think you should finish what you set out to do -with or without Jack Daniels help.

[GaspingGurami]

I used to feed boiled sweet potato to me shrimps. That created a bacterial bloom always, but the little ones loved it and showed their appreciation by multiplying, but I digress... The interesting thing that happened was the moss grew tremendously in this non-CO2 tank, taking over half of this 2fter's volume from its humble origins of a few strands tied to a twig the look and dimensions of one's outstretched thumb and index finger.

From then, I've been thinking about how sugar's breakdown by bacterial action can be simbiotic to growing water weed. I'm really glad Limsteel has the resolve and commitment to experiment in his tank. Thanks Lim for posting your observations.

[MatthewS]

Yes. Though I make a fun comparison to cold fusion, I actually think there is good reason to believe that adding sugar should work in some instances. Respect to your rough science and thank you for sharing the observations Lim.

I suspect that the sugar you add is not working directly as an algicide. Non CO2 tanks are co2 limited. The sugar you are adding is probably boosting the co2 levels in the tank as it is consumed by bacteria. That small amount of co2 may be boosting plant growth just enough to give it the edge over bacteria. In short it might be working in precisely the way Tom suggest you should focus - getting better plant growth. True you're probably not getting the 30PPM+ the CO2 injected pearling junkies among us are aiming for, but maybe enough that it would help the plants over the algae.

Think about DIY CO2 -we add say a cup of sugar and that produces a steady stream of CO2 for 3-4 weeks. That's anaerobic metabolism. The bacterial process in your tank is aerobic and I think that would probably produce more CO2 per unit of sugar than what's happening in the DIY CO2 bottle (Biology 101 is a distant memory but I think that makes sense - anaerobic metabolism leaves behind alcohol which is a complex organic molecule - ie unliberated co2). Also because the bacteria are actually in the tank you don't have to worry about all the junk in your tank like CO2 difusers / reactors. Bacteria breath Co2 out in such small amounts its disolved instantly.

This effect is not just limited to sugar. Any fish food be it pellets / flakes / boiled sweet potato etc..gets broken down by bacteria and respired as c02. I don't add anything to my tank but fish food, but CO2 levels are well above ambient levels. If I leave a glass of water out for a day or two the co2 levels are maybe ~5ppm. In my tank I think it's typically closer yo 10->15 PPM. Thats due to breathing fish, respiring plants and of course billions and billions of friendly, inivisible microbes.

Rgds Matthew