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| Salt water aquarium |
If you're a fish fan with a saltwater aquarium, you probably already know that you need to keep the specific gravity -- a proxy for salinity -- within a narrow range, and to do that you add fresh water to replace water lost through evaporation. Easy-peezy, lemon-squeezy, right? Well, not if you're "explaining" the process on eHow, where you're stuck padding things out to meet a minimum word count and you have to have at least three steps in the process. In that case – and especially if you're way out of your depth when it comes to basic science – you write utter rubbish like"Specific gravity (SG) refers to the density of various ions in the water. These ions are made up primarily of salts and minerals. The more ions in the water (in other words, the denser the ions are packed in the water), the higher the specific gravity." |
"...[The] denser the ions are packed..."? For real? It's an interesting daffynition of specific gravity, not to mention that Larry conflated specific gravity with salinity, a term he never even used! Moving right along, Parr explains that
Where Larry went wrong was in failing to understand what specific gravity actually is and how it's measured – the ratio between the density of a liquid and that of pure water at the same temperature (again with our researcher's "he never mentioned this" observation).
The whole time Parr was striving to get the details right he was overlooking the fact – obvious to an outside observer – that he didn't know what he was talking about; a situation compounded by the mistakes he made in basic math and science. If that's not the definition of a Dumbass of the Day, we don't know what is.
"...one of the primary concerns when determining the specific gravity of your tank is making certain that your hydrometer (the device that measures specific gravity) is properly calibrated to begin with."Which, of course, raises the question: how do you calibrate your hydrometer? Of course, you can't -- you just have to make certain the one you're using is calibrated for the temperature of the water in your tank, dumbass. Once he has that stupidity out of the way, Larry goes on to reword the instructions for using a hydrometer (carefully avoiding use of the word "meniscus," which he clearly didn't understand). Once that's out of the way, he instructs his readers to
"Add distilled or reverse-osmosis-filtered water daily to your tank to replace water lost to evaporation."OK, we'll go with that. It's when Parr tries to give an example that he falls victim to the above-mentioned phenomenon: he's apparently so careful not to make a mistake in rewording the instructions for adding water that he blows some awfully basic math:
"Adding 2 liters of clean water to a 200 liter aquarium (in other words adding .01% of clean water) will reduce the specific gravity of your tank by approximately 1%, or 0.00025."
 
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You gotta love it when people get confused by Demand Media's insistence on using the metric system... first, 2 liters is not 0.01% of 200 liters - it's 1%... and in what universe is 0.00025 one percent of 1.024? Off the top of our head, if the salinity is 32 ppt and you increase the water volume by 1 percent, the salinity would decrease by 0.32 ppt; in terms of specific gravity the value would change from about 1.024 to 1.02425. |
Where Larry went wrong was in failing to understand what specific gravity actually is and how it's measured – the ratio between the density of a liquid and that of pure water at the same temperature (again with our researcher's "he never mentioned this" observation).
The whole time Parr was striving to get the details right he was overlooking the fact – obvious to an outside observer – that he didn't know what he was talking about; a situation compounded by the mistakes he made in basic math and science. If that's not the definition of a Dumbass of the Day, we don't know what is.
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