Fishkeeping During A Heatwave

You raise a very pertinent question here Donna... 

As will be evidenced from another thread here, I am of the view that we fishkeepers probably change water far more often than we actually need to, as a general rule...  I can't imagine that a reduced water change regime, on a temporary basis, would do any real harm - but I lack the science to either reinforce or dispute this opinion... 

I still consider myself a relative newbie, so don't think that I have the experience to take a side on this, but I think you might be right that reduced volume water changes on a temporary basis may not do any harm.
I'm hoping that our very experienced keepers ( @Sue ,@fcmf ,@Hampalong and others) I'm looking to you guys to bring the science and the experience to the discussion, and give us relative noobs some solid advice, please. 

Thanks Sue - you posted while I was typing. 

Just looking up some info quickly, so can't guarantee the accuracy, but here goes:-
Water sprinklers usage = 550-1000L/hour
Flushing loo = 6-12L
Shower = 6-12L/minute

https://www.anglianwater.co.uk/_assets/media/Fact_File_5_-_Using_water_at_home.pdf

Well, for all the water change talk around at the mo, I've just done mine...   

I will admit that I have done water changes on 6 tanks this evening, so I think we can guess where I stand on this topic. The waste water was taken into the garden for the tomatoes, cucumbers, and raspberries.
I may cut back from 50% to 30% water changes on the largest tanks, but apart from that I plan to continue as normal, unless we have a problem with water supply in this area. 

I'm approaching this from a very different perspective. I moved in November and at present do not have fish. My tanks are gonna have to go in the conservatory so I've been sidetracking myself with the two lovely gardens while contemplating what fish to keep. It's a room with a plastered flat roof and full length windows - more of a 'sun room' maybe, but it gets very hot. There's a thermometer in there in constant shade that's going up to 90.

I also had a large tank in a true conservatory in '76. The tank got the sun through the corrugated plastic roof and sat at 86 for a few weeks. The water was like pea soup, but the fish all tolerated it ok. I was only 14 at the time and remember doing water changes with 'cold' water that was up into the 70s and didn't make much difference.

The only thing I can suggest is to have doors and windows open, tanks uncovered if it's feasible (meaning lid off), and fans blowing along the water surface or front glass.

The lives and health of my animals will always outrank a water usage restriction so I don't worry about water changes, but remember... nitrate levels are directly related to food input, so cutting down on the food you add will cut down on nitrates, allowing for less water usage. If the fish are uncomfortable they'll be less hungry anyway.

Water demand management is what what i did my masters dissertation on so here goes...

It's the rate of water usage which is most scary at the moment.  One stat I've heard is the in the North West half a billon litres of water more than normal are being consumed per day at the moment (might be as showers etc). If you look up reservoir levels, they are not especially low in many places, but are dropping fast and the dry weather is set to continue.

The concept of a water rush hour has also been introduced when everyone gets home from work, has a drink, shower, cooks etc etc. this places additional strain on the system, so I would also recommend thinking about when you are using your water. This is why some areas have seen low water pressures recently.

Another factor is leakage and whilst I don't want to get a debate started on this... Water companies have upped their investment into fixing leaks. There is an 'economic level of leakage whereby the leaks being fixed become so small and therefore comparatively expensive to solve each one (digging and detection costs stay the same) that there is little financial sense in fixing them in normal conditions. Now of course, water is worth more as demand is up and supply down so financially it becomes more viable to tackle smaller leaks. We can help water companies in their efforts here by reporting any leaks we may spot.

Personally I would encourage people to ensure they are reusing water as best they can as per the discussion here, using fish tank water in the garden etc. But when I was in South Africa recently (Google it if you don't know already, hut they have essentially run out of water) we had short showers but showered with a bucket. We used the bucket of water to flush the loo later or do the cleaning. People really were thinking about every drop of water as having multiple uses, thay water you washed your hands in is going back to a wastewater treatment works, could it not be used to fill the washer fluid in the car for eaxmple.  Car washing has riled me a bit in the below... surely you don't need to wash your car in this weather as it's not getting dirty?? Plus pressure washers do a terrible job of cleaning cars... (sorry ill get off the soap box). It also highlights for me the social standards which influence our water usage. I wonder if they are washing their car for themselves or so they can show their neighbours they have a shiny car...

Only full loads in the washing machine and dishwasher and switching off the tap when brushing teeth is advise always given at this time of year but my view is that people already know these things and whether they are doing them or not already, they are unlikely to change by being told again so hence my encouragement to think about showering with a bucket etc and how to reuse water. Other tips you won't often hear include microwaving veggies in a container with a splash of water rather than boiling them, buying bottled water (doesn't drain the local supply), fixing leaking taps (put a measuring jug under a leaking tap to see how much is being wasted), navy style showers (get wet, turn shower off, do th soapy bit, shower on to wash water off - better than a hot shower on a hot day!), let number 1s be flushed by the next person... One for the fishkeepers especially... collect your own free RO water by leaving a bucket out when rain is forecast!

To give my stance... I'm doing smaller water changes on a temporary basis (though I would add my tanks are all heavily planted). My lawn is also brown! I can't justify using more water myself for drinking etc if I'm not saving some in other places.

Rant over 

Reading Matt's post make me feel a lot less guilty about doing water changes.

Showers - that's how I always shower! I don't like getting my hair or face wet in the shower so I take the hand unit off the bracket and use it to wet my body then turn it off, soap myself, then rinse down.
Car washing - my husband uses a washing up bowl of car shampoo and a watering can of cold water to rinse.
Veggies - I use a pressure cooker which takes half a pint of water to cook them all in the same 'pan'. It also destroys fewer vitamins.
Washing up is done twice a day - supper, breakfast and lunch things after lunch, and dinner things after dinner. And they are washed in the sink though my husband does have a tendency to overfill the washing up bowl. The washing up liquid in the water is also good for killing greenfly in the garden.
Toilet - there's the Aussie saying 'if it's yellow let it mellow, if it's brown flush it down'.

@Matt Just a thought, we are not on mains sewerage and so we have a septic tank and soakaways, its a minor pain to have to have it emptied every three years and that waste still has to be processed but in principle is this a better system for the environment?
Obviously there is still the water supply side of the problem, and we should probably be harvesting and using grey water for flushing but the plumbing job would be rather extensive
The tank water is reused for planters however the grass is still very green as we are in Scotland, we don't really do brown

I understand that one of the ways to improve the efficiency of wastewater treatment is to separate surface water. It is only relatively recently that this has been done in the uk. It also means that flash floods due to heavy rainfall are less unpleasant.

There are also new plants that use the waste treatment process to generate electricity. Hence we get renewable energy and wastewater treatment has less environmental impact. Win - win.

My Dad is a (now retired) engineer who's specialty was wastewater treatment. It's the main reason why I'm consious of my water use and suspicious of beef tomatoes!