# Domestic hot water cylinder - is it harmful?



## Simon Cole (14 May 2019)

I am putting some serious wear on my father's kettle. It occurred to me that a better option might be to use water from our hot water cylinder. As I understand it, the cylinder is fed from mains water and heated by a central heating loop, it is also copper, and we are in a hard water area.
May years ago I was involved with drinking water analysis. I know that my shrimps and fish are likely to be intolerant to dissolved copper, but is this likely to be neutralised by Fluval water conditioner - or is this reversed back into free ions when the effect wears off? I also EI dose, there are now too many tanks for me to manage with a kettle. Is the hot water from this source safe? what are your experiences?  Any opinions would be gratefully received.


----------



## lazybones51 (14 May 2019)

Most houses have copper pipes for their hot and cold water, along with as you said a copper water tank. I expect the boiler has copper components as well. I've always just used the hot and cold taps for water changes and never had any issues, I imagine most people are the same.

It didn't ever occur to me to use the kettle for hot water.


----------



## Tim Harrison (14 May 2019)

Simon Cole said:


> Is the hot water from this source safe?


Yes it is. Otherwise we'd all be suffering copper poisoning, didn't realise there was any other practical way of doing things...
I think it all boils down to the residence time of the water in the system. It's very transient in most households, so there isn't time for too many copper ions to leach in to solution. If it was lead that might be a different story.
Looking at it from a different angle, I'm pretty confident I'm not going to get copper poisoning since my shrimp are fine...canary in a coal mine...


----------



## Simon Cole (14 May 2019)

That's great news. Thank you both.


----------



## ian_m (14 May 2019)

If copper pipes did dissolve in water, we would have had flooded houses as the pipes dissolve. Obvious really...

The green stains, often seen under old taps that have a drip, is dezincifacation of non water approved (WRAS) brass. The amount of copper, again, is very very small, but easily visible as green deposits on white enamel.

I can't use my house hot water, as it is softened and contains sodium carbonate rather than calcium and magnesium carbonate. Sodium salts have no place in fish keeping, but scale free showers and super soft water for washing is definitely worth it.

I use this to heat my water. Easy
https://www.ukaps.org/forum/threads/water-change-heater-project.25877/


----------



## alto (14 May 2019)

I doubt it is much different than most tap water conditioners (EDTA or similar is generally added)

eg, from Seachem Prime


> It will also detoxify any heavy metals found in the tap water at typical concentration levels.


----------



## rebel (15 May 2019)

Go forth and use ya hot water cylinder/tap!

For Caridina/Tiger breeding however, best to use RO. Neocaridina will be fine in your tap.


----------



## cdelly (15 May 2019)

Use hot and cold water, only time I dont is when using RO, in a tub with heater and power head for that one

Sent from my SM-G955F using Tapatalk


----------



## Aqua sobriquet (15 May 2019)

As the trend for quite some years has been to replace old HW and CH equipment with Combi Boilers I wonder how many houses still have hot water cylinders? Our current house has a Combi but the last two had stored hot water.


----------



## Andrew Butler (15 May 2019)

Make things even easier and fit a TMV - Thermostatic Mixing Valve under a sink, connect a hozelock fitting to it and then it's just a case of running the water straight from the TMV to the tank through a hose.
Fairly simple plumbing if you have half a knowledge about things.
You set the temperature you require on the TMV but if you go this route just check the TMV will go to the temperature range you desire.


----------



## ian_m (15 May 2019)

I found very few affordable TMV's that would go as low as say 24'C. Most reasonably cost ones are for mixing warm water for hand washing and too hot for fish.

However most quality thermostatic mixer shower valves do go low enough but a decent one will cost £150-£200.


----------



## Andrew Butler (16 May 2019)

https://smile.amazon.co.uk/Gangang-...hermostatic+mixing,aps,132&sr=8-1-spons&psc=1

This isn't the exact one I have but this is less than £30 and goes as low as 20'C - sorted!


----------



## Oldguy (16 May 2019)

Simon Cole said:


> water from our hot water cylinde



Our tap water is chlorinated and in common with UK tap water has phosphates added to prevent lead and copper leaching from pipe work. (Lead service pipes were in common usage up till about 1965) Our supply happens to be plastic.

Water enters the hot water system via a header tank in the roof and then into a copper hot water cylinder. Chlorine has dispersed on standing in header tank.

Water changes are 50% rain water, 50% hot water. No further additions of LFS stuff.

I actually add chelated copper as part of a trace element mix for the plants. Red Cherry Shrimps are fine and out breed fish predation.

Planning to spur off the hot water supply in the kitchen with a standard tap so that a hose pipe can be fitted. (mixer tap will not take a hose pipe to tap fitting, money down the drain, fitting in the spares box).

Hope this reassures you.


----------



## ian_m (16 May 2019)

Oldguy said:


> Water enters the hot water system via a header tank in the roof and then into a copper hot water cylinder. Chlorine has dispersed on standing in header tank.


Unless chloramine has been added which does not gas off upon standing. So as always dechlorinator MUST be used where water comes from the tap.

People have lost £100's of fish due to assuming letting water stand for 24hours (without testing as well !!!!) is good enough and water board have emergency added chloramine due to water pipework issues.


----------



## sparkyweasel (16 May 2019)

Many years ago, you could register with the water board as a fishkeeper, and they would notify you when there was any work of that nature going on.
It would be nice if they re-introduced that service in these days of automated text messaging.


----------



## Oldguy (17 May 2019)

ian_m said:


> So as always dechlorinator MUST be used where water comes from the tap.



Not all dechlorinaters will break the amine to chlorine bond. If your water is disinfected with chloroamine your fish are still at risk when using most 'water safe' products and have spent money for nothing. The more the source water has been filtered through kidneys the more likely that chloroamine has been used. There many parts of the UK where I would not live. Water companies can be a little coy about the use of chloroamine, but the kidney count is a good indicator.

My tap water is from a small local supply (part of a very big water company, but the water is very local) and I can hear, if the wind is in the right direction, the warning sirens when chlorine is being added at the treatment works.

[Of topic, wife & I do have our own gas masks (WW II re-enacters) and yes I am aware of asbestos in some filters]


----------



## Andrew Butler (17 May 2019)

ian_m said:


> Add full tank volume amount of dechlorinator to tank and add water, ensure filters are off etc


My method; not failed to date.


----------

