Do BTUs correspond to higher driftwood nutritional value?

[WyldFya]

I have been trying to figure out which types of wood are the most nutritious for wood-eating Loricarids like the Royal Pleco/Panaque. I haven't had much luck, and it is probably not important enough to spend a lot of energy on (pun intended). BUT, I am curious. I found a web page chart showing the caloric quantities of various woods expressed as BTUs. The chart is for people who want to get the most heat per cord of firewood. My understanding of how calories, btus, and nutritional value relate is very limited. I may be totally misinterpreting the chart, but I wanted to post it to see if anyone thinks it is useful for finding the best wood to feed Panaques and other wood-eating species of fish.
http://www.hearth.com/econtent/index.php/articles/heating_value_wood

I don't think the BTU's can translate to calories that the fish will use. Higher BTU could be due to many things, including higher oil content.

 

[knifegill]

No, Wyldfya. Hemlock trees do not contain toxic sap. Pine trees do for sure. Cedar is also toxic. If a species of wood you are using as food needs to be leached out to remove toxins, pick a different species. I'd never use a pine or most conifers, but hemlock is very safe. And easily edible, unlike many woods used in aquaria.

 

[WyldFya]

No, Wyldfya. Hemlock trees do not contain toxic sap. Pine trees do for sure. Cedar is also toxic. If a species of wood you are using as food needs to be leached out to remove toxins, pick a different species. I'd never use a pine or most conifers, but hemlock is very safe. And easily edible, unlike many woods used in aquaria.

Hemlock is a conifer, it is not good for your tank, particularly in the water parameter region. Most conifers do not contain toxic resins, but they are too soft, and rot, causing a large spike in nitrogen. This is very unhealthy for a tank.

 

[RodG]

Great thread guys! Some good info here.

 

[lujor]

I don't think the BTU's can translate to calories that the fish will use. Higher BTU could be due to many things, including higher oil content.

http://www.engineeringtoolbox.com/heat-units-d_664.html
This is why I was asking. I don't fully understand how/why the energy released by combustion is equal to the energy gained by consumption (ha!), but apparently it is. Energy is energy I guess. So what do you get if you multiply a Twinkie by the speed of light squared?

 

[knifegill]

Hemlock is a conifer, it is not good for your tank, particularly in the water parameter region. Most conifers do not contain toxic resins, but they are too soft, and rot, causing a large spike in nitrogen. This is very unhealthy for a tank.

If you put very large pieces in, yeah, it could be a problem. But if you're just prepping small pieces as food, it's not a problem. The plec eats the softest parts first. So, I agree with you and offer the reason it worked for me.

Yeah, BTU's are calories. If what's burning is the correct nutrition for the 'digester' in question.

This is why I was asking. I don't fully understand how/why the energy released by combustion is equal to the energy gained by consumption (ha!), but apparently it is. Energy is energy I guess. So what do you get if you multiply a Twinkie by the speed of light squared?

Theoretically, enough energy to power New York for six months.

 

[lujor]

If you put very large pieces in, yeah, it could be a problem. But if you're just prepping small pieces as food, it's not a problem. The plec eats the softest parts first. So, I agree with you and offer the reason it worked for me.

Yeah, BTU's are calories. If what's burning is the correct nutrition for the 'digester' in question.

Theoretically, enough energy to power New York for six months.

Are you saying that because your mind/memory is hybridizing Einstein & Ghostbusters? Yeah, I get the that all matter has energy you could harness by splitting the atom, fussion, fission, whatever, but I still don't fully grasp how cals and BTUs are the same but different. ??????

 

[knifegill]

A raw calorie is measured simply by burning and measuring the heat increase in a given amount of water.

What animals can use which calories varies wildly. We cannot digest cellulose, but it will burn and produce calories measurably. So yes, cellulose has calories, but not for humans.

 

[WyldFya]

If you put very large pieces in, yeah, it could be a problem. But if you're just prepping small pieces as food, it's not a problem. The plec eats the softest parts first. So, I agree with you and offer the reason it worked for me.

Yeah, BTU's are calories. If what's burning is the correct nutrition for the 'digester' in question.

Theoretically, enough energy to power New York for six months.

At which point it would be easier to actually use a coconut. Resins can cause many issues with both water parameters and equipment. A lot of what the pleco is eating from these woods is actually bacteria, not so much the wood itself.

 

[knifegill]

Bacteria? The caloric content of wood is in the lignins.

Here's something about how weevils digest wood. It may apply.

Pselactus spadix tunnels timber structures in the marine environment. Recent studies reported a cosmopolitan distribution for this weevil, which is frequently found in harbour and port areas. P. spadix feeds on timber (hardwood and softwood) in immature and adult life stages, but its digestion of wood components had not been investigated. Using dry weight analyses of tunnel walls and frass produced, P. spadix adults consumed Scots pine with soft rot decay at a rate of 1.59 ±0.37 mg d -1 and the digestibility of this substrate was 57.96 ±5.89 ( i.e. for 100 mg consumed SR-pine, 58 mg was digested). Using gravimetric analysis to quantify structural wood components in tunnel walls and frass, P. spadix adults were found to digest cellulose, lignin and hemicellulose with digestibility coefficients of 82.2, 41.2 and 14.5 respectively. Fourier Transform Infrared (FTIR) spectroscopy analyses of tunnel walls and frass of adults and larvae from soft rotted pine also indicated digestion of all structural components, with larvae digesting cellulose and lignin more efficiently than adults. When FTIR was employed to analyse adult tunnel walls and frass from undecayed pine, cellulose and hemicellulose were digested, but no evidence of lignin digestion was found. This study shows that adults digest lignin when soft rot is present and suggests a symbiotic function of wood degrading microorganisms.

Or we're both right!


http://www.informaworld.com/smpp/content~db=all~content=a753990997