i now have a heater controller with heater and chiller out puts. :bounce:

i am going to try hooking the chiller part into 2 pc fans via a small 12v transformer, and see if that will be ok before spending the huge cash a chiller costs.

would it be better to have the fans sucking or blowing air past the halides? i have a suround on the top of my tank that i will mount the fans into.

any ideas are welcome

blow

Sounds like a good idea . But I think you might get better cooling by blowing the water than the bulbs ? Last summer i had to get the fan blowing the hell out of the sump to keep it ok but it worked :roll:

Blowing provides a more concentrated stream over a longer distance.

Take the fan and use a piece of paper suspended and it will demonstrate the flow and concentration.

Another fairly powerful/free and often neglected means is using convection. Hot air rises... so by angling a hot surface slightly the hot air will flow and cause natural airflow. As the hot air rises it flows and cooler air replaces it... causing a gentle and silent flow. Used in conjunction with a well situated fan blowing one can improve cooling considerably.

I have also found that the common pc fans rev higher than the optimum speed. Basically they thrash the air causing lots of noise, slowing them down slightly reduces noise considerably with very little if any loss in fan performance. I typically use a cheap variable resistor find optimal speed I want for the fan then measure the resistance and put a suitable resistor in line. Viola, a quiet fan still working optimally. Just watch it as the cheaper fans will slow down with time due to cheap bearings etc so usually I allow just a touch more. Or leave the variable resitor on so you can dial it up or down as you require.

Hope this helps.

I wouldn't even bother with a transformer and PC fans. You can get small 240v fans from the Warehouse, like 6" or 9" fans for dirt cheap, they'll blow many times more air than a case fan will and be just as quiet doing it. I use a box fan that's maybe a foot and a half across to cool my tank. Cost me $30 at the warehouse, has been going about 9 hours a day for about 2 years now.

my high temp alarm went off yesterday, 30.2o at 5pm, had 2 pc fans hoked up and they had evaporated a heap of water but hadnt helped in cooling, i put a big fan pointing down towards the water surface, also put a frozen coke bottle into the sump.

it took just over 12hrs to come back to 24o, i will now see how today goes, lights have just come on but im at work so cant be sure of temp.

anyone got a chiller for sale? my guess is i will have to get one as we are no where near the summer months and already i have cooling problems.