[topwater1]

The CFT Canadian Open (Windsor, Ontario) used a most ingenious weigh-in method this year. It may not be new but it was new to me.
Someone got the bright but simple idea to weigh the bass in a WATER-FILLED basket/bin. Every fishless basket is tared zero for the basket/water weight and the fish are added. The difference is obviously the weight of the fish.
Brad McIntyre of the CFT took me through the system and explained that the fish are out of the water once to measure/check alive/count, momentarily as they are drained and put into the water basket and momentarily as they are dumped into the return holding tanks.
With the Shimano scales reading after a set period of no motion, they read almost immediately because the fish are not flopping around. The weigh-in went so smoothly and quickly, they had time to spare.
Just thought that I would pass this on. Tim J.

 

[Rono]

How big was the basket/bin?
They had no fish flop out, even with the water?
How big were the scales (compared to most that we use)?

Sounds interesting.

 

[Bronzeback5LBER]

This may be a stupid question,it isn't my first and probobly won't be my last.But here goes...... would there be a difference of the weight of the fish with the air bladder(of the fish) in working mode?The reason I ask is the fish float to the top of the water (if its filled with air)that would make them lighter than water true or false?If this is a stupid question than lets act as if I never asked it,but if its a good question tell me. Also I know it would register some weight because of the body of the fish displacing the water,but would it register the true weight?

 

[Alex]

Ahh a brain teaser. Being an engineer geek I can probably answer that. Although I'm sure I can't explain in well. In a closed mass system, it would not matter. The mass of the fish added to the mass of the water would still be creating a downward force on the scales (hence your weight). The fish floating means that it is able to displace the same amount of water weight as the fish. But since they are both on the scales it is a combined system. Think of this way, if you put your boat in the same tank of water (use your imagination for that one) would it register the weight even though it floats? Pretty freaking clear huh?

One of my favorite engineering geek arguements is this. If you have a butterfly in a closed jar, does the weight increase, decrease, or remain the same if the butterfly is flying or resting on the bottom? I await your answers. Heck, I even forget the correct answer sometimes.

 

[topwater1]

If the butterfly is not touching the jar at all, it does not change the weight of the jar. The medium of air is not fluid and does not transfer weight.

Alex, you are correct in that the medium of water transfers the weight of the fish as part of the total weight, just as if they laid on the bottom of a dry basket.

BB5, displacement would only register volume, not weight.

Rono, the basket was not much bigger than a standard weigh-in basket. Remember, the fish were upright. The scales had a normal-sized platform, about 1.5-2 ft. square I'm guessing.

Tim J.

 

[djkimmel]

Brad was telling me about this system. It sounds very interesting. I've got to see it sometime.

Alex, you should be severely punished for posting that kind of stuff on a board like this...what where you thinking. I have a headache now. Next thing, you'll be asking what weighs more - a 4 pound smallmouth or a 4 pound largemouth?

 

[madman24]

im still waiting for the age old question ' if a tree falls in the woods, does it make a sound ' to finally be answered.

my question is:

how do they ensure that the exact amount of water is in the tank for every bag of fish? certainly they would loose some water here and there. and even 1oz of water would be near impossible to notice missing in a tank the size of an average weigh in basket.

madman himself

 

[madman24]

wow, its early. disregard that last question and please dont hold it against me

madman himself

 

[Alex]

I know Dan, I was regretting it the moment I typed it. My sole purpose was to see if I could confuse you, apparently it worked!

By the way, topwater1, "The medium of air is not fluid and does not transfer weight." is incorrect. If it were true the butterfly could not fly at all. The correct answer (for those that care) is: it doesn't matter if the butterfly is flying or resting on the bottom of the jar, the weight would be the same. I'll spare you all the explaination. But who knows, I could be wrong, heck I think the answer to Dan's question is obviously the 4lb smallmouth!

 

[No More Mini]

The weight of the fish would be skewed due to the specific gravity of the water....at least thats what my old engineering brain remembers....just as you dont weigh the same on the moon as you do here.

as far as the butterfly in the jar.....heck let em loose!

Mini

 

[topwater1]

Alex: I want to argue this one but for the betterment of everyone's mental state, this time, I will let it go.

Mini: I thought about that also but the actual weight of the fish is a constant. Dump a 3lb. bass into a tank of water and the total weight of the tank increases by exactly 3lbs.

Mac: will you be off during the week of Aug.17-23? If so please drop me an e-mail direct. Maybe we can explore.

Happy fishing all. I'm off to Simcoe/Couchiching/Sparrow Lakes for the week.
Tim J.