Hi. I just recently put a heater in one of my tanks because my fish is ill. I also want to do daily waterchanges because I had a spike in my cycle due to moving. My question is: How do I match the temperature of the water that I am replacing with to the water that is still in tank, during waterchanges?

The temperature difference is quite big. Room temperature water is about 70 and his tank water is about 78.

Is there an easy way of doing this? Or should I not use the heater?

Thanks! Brittany

If the PH of the water from your tap matches the PH of the water in your tank, just adjust the temperature of the water coming out of your tap to the temperature of the water in your tank, (I use a cheap instant read digital thermometer) fill a bucket, add dechlorinator and do a water change.

If you're using a python or similar device, match the temperature, add enough dechlorinator for the entire volume of the tank and do the water change.

If you have to let water sit out so the PH can stabilize, you can take some water from the buckets of stabilized water, heat in a microwave or on the stove and add it back to the buckets of stabilized water. Knowing how hot to get the water you're heating so that it rises the temperature in the bucket to match the temperature in your tank is easy.

I use this formula for matching the temperature of the water in any size container.

([total ounces of water in the container] X [tank temperature]) = ([ounces of water left in the container] X [container temperature]) + ([ounces of water removed from the container] X [temperature of water to rise container to tank temperature])

For example: you have a 5 GA bucket of 70 degree water and want to raise it to 78 degrees. You have removed five cups of water from the bucket and put it on your stove and want to know how hot to get it.

(640 x 78) = (600 x 70) + (40 x ?)
49920 = 42000 + (40 X ?)
49920 - 42000 = (40 x ?)
7920 = (40 X ?)
7920/40 = ?
198 = ?

So you want to heat the water on the stove to 198 degrees.

Or even simpler: You have a 5 GA bucket of 70 degree water and you want to raise it to 78 degrees. You have removed 1 GA of water and put it on your stove and want to know how hot to get it.

(5 x 78) = (4 x 70) + (1 X ?)
390 = 280 + (1 x ?)
390 - 280 = (1 X ?)
110 = (1 X ?)
110/1 = ?
110 = ?

I generally just use the microwave and heat up a portion of the water until it matches the temp of the tank to within a degree or two.

Wow! Can you help me with my trigonometry too?! hehe Nice formula. I'll try it. Thanks for all the help, it'll make things a lot easier for me