Weekly Water Change - Obtaining The Right Water Temperature

[rust81]

Although i am not new to fish keeping and have had my first tank for just over a year now, i have a bit of a random question, so here goes:

When doing my weekly/bi-weekly 10% water change, I normally use tap water plus some water from the kettle in order to get the correct temperature. As the pH of my tap water is high and therefore so are my tanks (pH = 8.0) i thought i would look into this a bit more. After running my cold water tap for 3 minutes or so, i measured the pH which came out about 7.5. However when i add the boiled water from my kettle to this - it ups it to around 8.0. So my question is - whilst boiling the water - does this do something to the dissolved minerals that alters the ph? If so, how else can i get my water change to the correct temp?

 

[Ian H]

you may want to post this in the scientific (sp??) section. I do exactly the same and never really thought about it tbh. The only thing i know that lowers ph is CO2

 

[backtotropical]

As kettles are used, they develop a limescale build up on the elements. This will dissolve slightly in the water every time the kettle is boiled and will make the water slightly harder and raise the PH.

With regard to matching temperature, i wouldn't bother too much. I used to but learned on this forum that it's really not necessary. The fact is, the fish we keep will suffer much bigger temperature fluctuations in their natural habitat than they do in our aquariums.

Some fish like Corydoras will actually swim in the flow of cooler water and it can actually encourage them to spawn.

Neither the slight change in temperature or PH should be a problem for most fish.

Hope this helps.

BTT

 

[Ian H]

so does this mean i can do a 10 - 20% water change on my tank with cold water from the tap instead of making it warm/room temp with the kettle?

i thought the sudden change in temp would put the fish into shock

 

[blue acara]

A 10-20% water change with cold water will not effect the tanks temperature very much at all. It is generally stated that a 2dC temperature change is fine for fish.
If you are changing a large amount of water say 40-50% or more you should heat the water first.

 

[backtotropical]

Yes. Temperature shock can happen to fish, just as it can happen to humans, but it would require a large temperature swing, much larger than the temp changes in your tank whilst performing a water change. As i said above, most fish will endure much larger temperature fluctuations in their natural habitat with no ill effects.

You will find that if you use cold water from the tap the fish actually like it. Many fish will swim and play in the current of cool water, and it will encourage some species to spawn.

I do it without temperature adjustment for up to 50% water changes (and the water from my tap is COLD!!).

Above 50%, i would maybe leave the water to warm up a bit for an hour or so, just to be sure, although i believe some members here will use unheated tap water for up to around 75% changes.

Certainly for routine tank maintenance the temperature change seems to have a positive effect on the fish rather than inflicting the commonly believed temperature shock.

Cheers

BTT

 

[vinylman]

The only thing I'd avoid when changing water is to have the new water noticably warmer than the tank water. I always go by hand; if it feels close, then that's close enough. The bonus of making the new water slightly cooler is that you may actually get your fish 'in the mood'.

 

[SamLovesCorys]

You guys have no idea how helpful this is to me!