Filtered Tap Water For Partial Water Changes?

[Spitzy]

Hello all.
I have just joined up and had a quick read and there is a lot of great info on here!

One question I have not been able to find the answer to is whether filtered tap water is good for my aquarium.

I have a 126L community, platys, black neons, corys, lemon tetras etc no live plants. Last year I had an under sink water filter installed in my house after reading the composition of my local (Norfolk) water supply which contained a lot of nitrates, chlorine etc compared to my friends water supply in Bedfordshire. As this filter manufacturer claims that the filter removes 99%+ of nitrates, metals, chemicals and chlorine is this water ideal for my partial water changes?

Ta Spitzy

 

[kelvinrankin767]

Its very simple provide your fish with the best possible water so idealy do water changes with your filtered water.

 

[Spitzy]

Its very simple provide your fish with the best possible water so idealy do water changes with your filtered water.

Ok thanks for the reply. I just didn't know if there was something/anything in tap water beneficial to my fish that may be filtered out.
Spitzy

 

[Bignose]

Depends on what the filter filters out. Does it soften the water? If so, it may be removing calcium and magnesium that your fish and plants could use, and replacing them with unusually high levels of sodium. There are other micro nutrients that are in the water that live plants can use -- iron, manganese, etc. Again, if you filter is removing these, you may not want that.

I guess what I am saying here is that in order to answer this question well, more information about the filter really is needed.

 

[Spitzy]

I have had a look at the water filter site and the model I have uses coconut shell extruded carbon and some sort of anti scale media. As far as i can see it does not add anything to the water.
It removes
Chlorine 99%
THM's (trihalomethanes) ECB's, OCB's, TME's 90% to 99%
Pesticides 90% to 99%
Herbicides 90% to 99%
Industrial Solvents (halogenated hydrocarbons) PCB's (polychlorinated biphenyls) PAH's (polycyclic hydrocarbons) 90% to 99%
Discolouration 95% plus
Rust Particles, Silt, Algae 99%
Benzene, Petroleum Solvents, Oil Residues, 85%

I don't know what my fish will think of it but I know it tastes a whole lot better

Spitzy

 

[anon02]

If you buy your fish locally it is likely that they have become acclimatised to your local water, before you buy any fish ask the seller if he uses treated water
Another consideration is what happens if your filter is inoperative for some reason when you need a water change. I think it`s true to say that most experienced fishkeepers prefer not to mess with their water chemistry, but rather buy fish that will thrive in their local water supply

 

[raptorrex]

If you buy your fish locally it is likely that they have become acclimatised to your local water, before you buy any fish ask the seller if he uses treated water
Another consideration is what happens if your filter is inoperative for some reason when you need a water change. I think it`s true to say that most experienced fishkeepers prefer not to mess with their water chemistry, but rather buy fish that will thrive in their local water supply

well put, and utterly true!

 

[OldMan47]

I have had a look at the water filter site and the model I have uses coconut shell extruded carbon and some sort of anti scale media. As far as i can see it does not add anything to the water.
It removes
Chlorine 99%
THM's (trihalomethanes) ECB's, OCB's, TME's 90% to 99%
Pesticides 90% to 99%
Herbicides 90% to 99%
Industrial Solvents (halogenated hydrocarbons) PCB's (polychlorinated biphenyls) PAH's (polycyclic hydrocarbons) 90% to 99%
Discolouration 95% plus
Rust Particles, Silt, Algae 99%
Benzene, Petroleum Solvents, Oil Residues, 85%

I don't know what my fish will think of it but I know it tastes a whole lot better


What you have is a simple carbon filter with some mechanical medium added. It is fine for pretreating your water for the fish since it only really removes organics and solids. Unlike an RO unit, it is not removing anything but solids so the end result water will measure about the same as what goes into it except for the visible particles and the organic poisons.
Do not use that water as a top off water. That will result in gradually increasing the dissolved minerals in the tank water. Instead you want to do a water change so that you remove some of the existing minerals in the tank before adding them back in with the new water. Top off water should be devoid of all chemicals since it would otherwise raise your TDS. For that purpose I use RO water.