hot or cold water changes

[screaminleeman]

I have a well and am able to pump water directly from the sink to my tanks. I generally prefer ever so slightly warmer water replacement. I just get close. I will seriously counter the "close is OK thing though"!

It is NOT ok for all species. I have probably killed 100 clown loaches in dozens of different water changes not maintaining a 5 degree F variance. Had bad results with this for Rams also!

 

[FormulatedFire]

In my opinion the answer to this question can vary depending on a couple factors. The first factor is what size tank are you using, and secondly what size water change are you doing? If you are doing a 12.5g (10%) water change on a 125g tank a small change in temperature +/- 5 degrees will not be a major effect, but if your doing a 62.5g (50%) water change on a 125g tank the temperature change will be felt a lot more by the inhabitants.

The easiest way I found to keep water change temperatures the same while maintaining a quick and easy swap is to pick up one of those laser thermometers that are mainly used for HVAC. All you have to do is point the trigger at the water and it shows up the temperature in a nice little digital read out.

Here is the one I have:
http://www.google.com/products/cata...u0gHPg7iVBA&sqi=2&ved=0CIoBEPMCMAA#ps-sellers

 

[Cicho]

In the Summer I add water cooler than the tank. In the Winter I add water that is warmer than the tank.

Reason is that I rarely run heaters in the Summer but have to run heaters in the Winter.