Weird Whirlpool Thing In My Tank?

[tat2life]

hey guys
im running a 2ft tank with nothing in it at all other than gravel/sand a heater, pump and salt in the water. around my heater about 1/2inch above the gravel there is a whirlpool looking thing in the water... like when you look at a fire you can see the hot air above it.....it looks like that. any ideas what it is?

 

[xxBarneyxx]

Yeah if your heater is on then its the warm water rising from it.

 

[tat2life]

ah thanks, is it dangerous or anything? or any ideas how to get rid of it.. heater has been on for 4 days now

 

[jtnova13]

if it is causing a noticeably movement, it could be causing that patch of water to have a big enough difference in temp to kill a fish maybe.

maybe aim a powerhead over there to move water past the heater so there are no hot spots? Maybe it will stop doing that once the water is at the correct temperature. Water has a pretty high specific heat, so i assume a heater that small wont be able to click on and heat water that fast once it reaches the steady state temp.