Water change - too hot or too cold?

Fishy_Dan

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I have a JBL aqua in/out for water changes (German version of a Python). It's great, but as a one man job it's not possible to adjust the water temperature while filling the tank. I'm too scared to leave the pipe incase it falls out and pours water everywhere.

It's not easy to get the tap water to come out at tank temperature from the tap. I can get it close, but after the water change the tank can change by +/- 3 to 4 degrees.

So what would be better? To fill it so it ends up a little too cold or a little too hot? Usually it's set to 24 degrees.
 

HoldenOn

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I have a JBL aqua in/out for water changes (German version of a Python). It's great, but as a one man job it's not possible to adjust the water temperature while filling the tank. I'm too scared to leave the pipe incase it falls out and pours water everywhere.

It's not easy to get the tap water to come out at tank temperature from the tap. I can get it close, but after the water change the tank can change by +/- 3 to 4 degrees.

So what would be better? To fill it so it ends up a little too cold or a little too hot? Usually it's set to 24 degrees.
I'd say cold. Similar to a tropical rain. However that is a really big fluctuation, is there any way you could get someone to adjust the tap temp.?
 

Ch4rlie

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Cooler water while refilling the tank is always better imho.

Be almost like rainy season for the livestock always cooler waters coming in.
 

AbbeysDad

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As mentioned, a few degrees either way is no big deal and perhaps a bit cooler emulates a cool rain. But some food for thought... I got my tap running into a glass and adjusted the hot and cold to get the desired temperature. I then marked the side of the faucet handle with a sharpie, so I know exactly where to set it every time....works like a charm.
 
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Fishy_Dan

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Problem is that the temperature changes over time while the tap is running. So I can set it off about right but then the boiler kicks in or out. Also depends on how fast the flow is.
 
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Fishy_Dan

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On a similar subject, as I'm adding tap water direct to the tank from the tap I add my dechlorinator while it's running. So some water goes in there while there's no dechlorinator.

I assume this is fine, but then wonder why people say washing filter media will kill bacteria? Maybe sort term exposure is ok?
 

AbbeysDad

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On a similar subject, as I'm adding tap water direct to the tank from the tap I add my dechlorinator while it's running. So some water goes in there while there's no dechlorinator.
I assume this is fine, but then wonder why people say washing filter media will kill bacteria? Maybe sort term exposure is ok?
I have untreated well water so it's a non-issue for me, but I have to wonder why you don't add the conditioner just before you begin the refill.
As far as the filter media, folks get ultra conservative and some still believe that all the beneficial bacteria lives in the filter. In fact, in the established tank there's far more BB in the substrate and decor. That being 'said', the filter media could be cleaned in regular tap water and it would be fine. Some BB would be lost, but not enough overall to create an issue. The only exception would be in the still cycling or relatively new tank where filter bacteria is more important. Byron's article on my Blog, Bacteria in the Freshwater Aquarium points all this out very well. (Byron has stated here a few times that he always cleans filter media in tap water).
 

itiwhetu

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I think best practice is to clean filter pads in tank water and try to reduce the amount of gunk by 50%. But I'm guilty of running it under the tap as well
 
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Fishy_Dan

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I have untreated well water so it's a non-issue for me, but I have to wonder why you don't add the conditioner just before you begin the refill.
As far as the filter media, folks get ultra conservative and some still believe that all the beneficial bacteria lives in the filter. In fact, in the established tank there's far more BB in the substrate and decor. That being 'said', the filter media could be cleaned in regular tap water and it would be fine. Some BB would be lost, but not enough overall to create an issue. The only exception would be in the still cycling or relatively new tank where filter bacteria is more important. Byron's article on my Blog, Bacteria in the Freshwater Aquarium points all this out very well. (Byron has stated here a few times that he always cleans filter media in tap water).
Thanks for the link. An interesting read!
 
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