Physics Question!
A submerged heater is used in an aquarium to keep the water above room temperature. Should it be placed near the surface of the water or near the bottom to be most effective? Why?
It would be the bottom right?
A submerged heater is used in an aquarium to keep the water above room temperature. Should it be placed near the surface of the water or near the bottom to be most effective? Why?
It would be the bottom right?
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The bottom because heat rises. Especially in water!
The heated water from the lower level rises to the upper level... then when the upper level cools, the water will circulate the cool water back towards the bottom again.. this causes a natural current that heats the water more effectively.
If the heater was placed on the top.
Then the heated water would lose energy to the atmosphere and the lower levels of the tank will remain colder.... Its like going to the beach.... the sun warms the upper surfaces of the water... but if you swim deeper.. there is nothing warm down there, so the water remains colder.
In a heated pool... water is warmed through a water heater and the warm water is pumped into the pool (usually through holes in the bottom or side) If you ever swam in a heated pool... its warm through most of its entirety.
I hope this answers your question.
The heated water from the lower level rises to the upper level... then when the upper level cools, the water will circulate the cool water back towards the bottom again.. this causes a natural current that heats the water more effectively.
If the heater was placed on the top.
Then the heated water would lose energy to the atmosphere and the lower levels of the tank will remain colder.... Its like going to the beach.... the sun warms the upper surfaces of the water... but if you swim deeper.. there is nothing warm down there, so the water remains colder.
In a heated pool... water is warmed through a water heater and the warm water is pumped into the pool (usually through holes in the bottom or side) If you ever swam in a heated pool... its warm through most of its entirety.
I hope this answers your question.
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I'd say the middle
Just like air, hot water rises to the top of the tank by convection because it is less dense. If you place the heater at the top of he tank then the thermostat in the heater will soon detect that the water around it is warm enough and shut down the heater leaving all the water below it cold.
However, if the heater is placed at the bottom of the tank the heat will rise to the top of the tank as before and this will be replaced by more cold water around the heater. Sensing the water around it is still cold it continues to put out heat until the temperature at the bottom of the tank is warm enough for the thermostat to kick in and shut of the device.
Having said that, those heaters are not exactly accurate devices. I would suggest that is is best to placed the heater half way down the tank instead. Then, if the water is heated hotter than is indicated on the the dial setting then a least the fish ( I assume fish) would have the opportunity to go under the level of the water that is too hot for them and swim instead in a cooler region of the tank. That way the fish can swim at a depth that suits them. Never taken anything as given. In other words just because the dial says 20 deg do not take it as read. Give your fish a choice where to swim as not all like the same temperature. You will often find that these heaters come with sucker attachments to help secure them to the side of the tank.
Buy an accurate thermometer not one of those LCD stick on devices, but one that goes into the water. Alcohol base one not mercury!
Just like air, hot water rises to the top of the tank by convection because it is less dense. If you place the heater at the top of he tank then the thermostat in the heater will soon detect that the water around it is warm enough and shut down the heater leaving all the water below it cold.
However, if the heater is placed at the bottom of the tank the heat will rise to the top of the tank as before and this will be replaced by more cold water around the heater. Sensing the water around it is still cold it continues to put out heat until the temperature at the bottom of the tank is warm enough for the thermostat to kick in and shut of the device.
Having said that, those heaters are not exactly accurate devices. I would suggest that is is best to placed the heater half way down the tank instead. Then, if the water is heated hotter than is indicated on the the dial setting then a least the fish ( I assume fish) would have the opportunity to go under the level of the water that is too hot for them and swim instead in a cooler region of the tank. That way the fish can swim at a depth that suits them. Never taken anything as given. In other words just because the dial says 20 deg do not take it as read. Give your fish a choice where to swim as not all like the same temperature. You will often find that these heaters come with sucker attachments to help secure them to the side of the tank.
Buy an accurate thermometer not one of those LCD stick on devices, but one that goes into the water. Alcohol base one not mercury!