The Fishless Cycle - with sugar???

[neilanh]

As some of you know, I'm currently in the middle of a fishless cycle on my 46 gallon bowfront tank (FW). See the thread here if you're interested.

Today, I was over chatting with the manager at my LFS about ordering me some fish, and he was excited to hear that I was doing a fishless cycle. He asked me where I was in the cycle, how I was doing it, ammonia source, etc. Then, he brought up an interesting point that I haven't heard of or read about. Add sugar.

He explained this to me some, and to the best of my recollection, he stated that the addition of sugar (for my 46 gal tank, he suggested about 1/2 packet) somehow helps to synchronize the cycle in the charcoal with the nitrogen cycle, since sugar is a carbon source anyway. He claims this gives an added boost to running the fishless cycle, and that he does this on all of his QT tanks when he resets them to get things up and running quickly.

Anyone ever done or heard of this?

 

[tropicalfish]

I would not add sugar... but thats just me.. I would add fish food..

 

[JDogg]

He explained this to me some, and to the best of my recollection, he stated that the addition of sugar (for my 46 gal tank, he suggested about 1/2 packet) somehow helps to synchronize the cycle in the charcoal with the nitrogen cycle, since sugar is a carbon source anyway. He claims this gives an added boost to running the fishless cycle, and that he does this on all of his QT tanks when he resets them to get things up and running quickly.

that sounds like compleat rubbish to me...i would not try it... sounds like a cool science project though... but i would not try it on a tank i intended to put fish in

 

[neilanh]

Be leary in that I may have not regurgitated his information properly. I'll ask him to explain it in an email that I can post.

But has anyone even ever heard of this?

 

[rich311k]

I have never heard of adding sugar. I really cannot imagine what good it would do.

 

[tropicalfish]

I think... the only thing it will do is attract a big bunch of mosquitoes during the summer...

 

[theotheragentm]

Sugar wouldn't help the cycle as far as I can tell. It would dissolve, but it would still be sugar. It wouldn't be adding any sort of decay to the mix like a piece of raw shrimp or some fish food. I'm definitely interested in hearing the reasoning behind this. Maybe it's something that may work.

 

[neilanh]

I emailed him and asked for him to explain it to me again. Who knows, maybe this is a great secret to really speed up a cycle

 

[STARFYRE]

Nope. Never heard of it either. And I sure wouldn't do it. I'm not a fan of throwing foreign substances in my fishtanks. I don't even like to use aquarium additives (i.e. cloud remover, ammonia blockers, ph adjusters). I'd rather go as natural as I can. With my luck, my fish would get diabetes or something. I'd be dosing my tank with insulin every other week lol!

 

[rkilling1]

We are quick to dismiss something that we don't know about.

After researching this for a little bit, I have found some information that adds some validity to this.

Here is a little passage from Tom Barr:

"If you want to see if this occurs in nature, they will often add glucose as
a source of carbon and then measure the Denitrification rates. If they are
higher, then it suggest carbon limitation.

Where is that Roger Miller adding sugar to his tanks? "

From: http://fins.actwin.com/aquatic-plants/month.200402/msg00501.html

I am not saying we should all add sugar to out tanks, but I think we need to research subjects before jumping to a conclusion.

My take is: why not add Excel if you want a Carbon additive?

 

[bs6749]

The thing is... table sugar IS NOT glucose. Table sugar is SUCROSE. The two are not the same at all. Ex. Humans can digest sucrose but NOT glucose.

 

[JDogg]

it did suggest it as a cool science project...just a little nervous about additing to a tank i plan to add fish too :?

 

[rkilling1]

The thing is... table sugar IS NOT glucose. Table sugar is SUCROSE. The two are not the same at all. Ex. Humans can digest sucrose but NOT glucose.

Sucrose is the combination of glucose and fructose.

 

[bs6749]

Sucrose is glucose and fructose that are actually bonded together by a glycoside bond. It is not just a mixture of the two. With this bonding can arise very different chemical properties. Take for instance H2O. It is not just a mixture of H and O molecules. There is a specific ratio. 2 H for every 1 O. H2 gas is highly volatile under a flame and O2 is flammable as well. But when the two are bonded you end up with water (in that ratio) which is not flammable at all and has VERY different properties from the two in the first place.

 

[O ALX O]

SWEEEEEET!

 

[rkilling1]

Sucrose is glucose and fructose that are actually bonded together by a glycoside bond. It is not just a mixture of the two. With this bonding can arise very different chemical properties. Take for instance H2O. It is not just a mixture of H and O molecules. There is a specific ratio. 2 H for every 1 O. H2 gas is highly volatile under a flame and O2 is flammable as well. But when the two are bonded you end up with water (in that ratio) which is not flammable at all and has VERY different properties from the two in the first place.

When you add Sucrose to water, it breaks down into glucose and fructose. FWIW, H2O is held together by a hydrogen bond, which makes seperating it very difficult as compared to other compounds.

"When sucrose is hydrolyzed it forms a 1:1 mixture of glucose and fructose."

From: http://www.elmhurst.edu/~chm/vchembook/546sucrose.html

 

[jsoong]

When you add Sucrose to water, it breaks down into glucose and fructose. FWIW, H2O is held together by a hydrogen bond, which makes seperating it very difficult as compared to other compounds.

"When sucrose is hydrolyzed it forms a 1:1 mixture of glucose and fructose."

Er ..... Although sucrose is hydrolysed to glucose & fructose, this does not happen just by adding it to water. All you are getting is simple dissolving of the sucrose into water. To break the bond, you need an catalyst, which in living system is an enzyme. <BTW - humans CAN digest sucrose, glucose, fructose, galatose & a hosts of other sugars .... that's why we are getting fat from all the sugars we are eating .... some sugars - like suculose - we cannot digest - that is used for diet pop & such.>

To clarify one more point - H & O in H2O is held together by a chemical bond & is NOT easy to break. Different water molecules are held together with hydrogen bonds (forming liquid water), and that is weak & easily broken. You break that by heating (& turn water into steam!) Dissolving something into water means that something is held in solution by the same hydrogen bonds. The presence of hydrogen bonding is what makes water such a good solvent.

Back to the original post - I am not sure what glucose/sucrose will do to the cycle, apart from acting as food for yeast or maybe other bacteria ... tthe waste (CO2 or alcohol?) may facilitate the growth of the nitrifying bacteria. This may make a good experiment .... but I will remain skeptical.

And I don't see glucose as a carbon source for plants (like Excel). Glucose is the final product of photosysthesis. It is kinda pointless to use your finished product as your building block.

 

[rkilling1]

To clarify one more point - H & O in H2O is held together by a chemical bond & is NOT easy to break. Different water molecules are held together with hydrogen bonds (forming liquid water), and that is weak & easily broken. You break that by heating (& turn water into steam!) Dissolving something into water means that something is held in solution by the same hydrogen bonds. The presence of hydrogen bonding is what makes water such a good solvent.

My head isn't working. It's more like a polar covalent bond that makes up water.

 

[neilanh]

Well, this is spawning some interesting discussion. I emailed the guy and ask for him to explain it again, so that I can post it here when I get it.

 

[bs6749]

I don't know what I was thinking about when I said that glucose can't be dissolved by humans. I was thinking cellulose and not glucose.

Nice explaination about hydrogen bonding jsoong. Hydrogen bonding is NOT the interactions of the atoms in the same molecule with one another but rather their interaction with atoms on different molecules.