# excessive water changes?



## deadlus3d (9 Sep 2020)

Hello,

I was wondering if a weekly 50% water change is too much for my tank.
Could such a change alter the chemistry of the water too suddenly or is it advisable to change 50%?

Most info on the web is around the 10% 25% mark.

Regards,


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## sparkyweasel (9 Sep 2020)

If you do the changes every week the water in your tank will not have changed very much so there won't be a big sudden change. If you have been doing smaller, and/or fewer water changes your tank water may be very different from your tap (or other source) water. So, if you're thinking of changing your wc routine it's a good idea to make the change gradually.
50%/week is normal for a hi-tech with EI dosing; in lo-tech you have a lot more leeway.


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## Tim Harrison (9 Sep 2020)

I doubt it'll make much in the way of difference to water chemistry. But I'm sure your critters will appreciate the fresh water, and it'll help deter algae.
I often do a couple of 90-80% water changes a week.


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## Zeus. (9 Sep 2020)

Depends on if your running a high tech or low tech tank.

Low tech you fine with 10-25%, my low tech I just top up with RO and WC few times a year - but low light

But high tech esp with high light and EI dosing 50% is strongly advised esp in mew setup, I sometimes do an 80-90% WC after a big trim in my 50l.

Also depends on biomass, higher the biomass the more Dissolved Organic Compounds (DOC) you will have so a larger amount of toxics in tank esp if high light.

Monitoring the TDS can be helpful as well and just keep an eye on it.


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## deadlus3d (9 Sep 2020)

thanks for the replies.

what is TDS?


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## Zeus. (9 Sep 2020)

deadlus3d said:


> thanks for the replies.
> 
> what is TDS?



TDS meter


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## Conort2 (9 Sep 2020)

To be honest I’m of the opinion that you can’t do too many water changes. Low tech or high tech I’d recommend 50percent a week, it’s good for the fish and they love the fresh water. 

Cheers 

Conor


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## Luketendo (10 Sep 2020)

Even the high tech lean dosing route suggests 30 to 50% water changes weekly.


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## rebel (10 Sep 2020)

50% FTW!

I do 60% because my pvc attachment is setup like that.

It is still not enough because in the wild, there is 100% water change per second not 50% per week.


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## LondonDragon (10 Sep 2020)

At the moment I perform two water changes a week between 70-80% everyone is happy and algae is now staying away! happy days


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## dw1305 (10 Sep 2020)

Hi all, 





sparkyweasel said:


> If you do the changes every week the water in your tank will not have changed very much so there won't be a big sudden change.


I usually do small regular water changes, it suits me because it allows the rain-water to warm up over night before I use it in the morning. It also trickle feeds _Daphnia_ etc. The water is often still appreciably cooler than the tank water, but some of the <"fish associate water entering the tank with food">.

If I've been away from the tanks I do a much  bigger (or more frequent) water change(s) until I get back to somewhere <"near the conductivity datum level">. 

I've never had any problem with this, but the rain-water won't be much different in chemistry from the tank water.

cheers Darrel


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## Ags11 (10 Sep 2020)

I do 33% per week - that is what fits in a 10_l_ watering can!


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## dw1305 (10 Sep 2020)

Hi all, 





Ags11 said:


> that is what fits in a 10_l_ watering can!


I use re-cycled 3.4 litre (6 pint imperial) milk containers, it is quite interesting how long a "single use" plastic bottle can last before leaking.

We have been having milk delivered (in smaller bottles) since the end of March and I'm still using most of the milk cartons that pre-date this. A few I've has so long that they have grown a good crop of _Acroloxus lacustris. _

cheers Darrel


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## rebel (17 Sep 2020)

dw1305 said:


> it is quite interesting how long a "single use" plastic bottle can last before leaking.


And sobering. I feel guilty everytime I throw a milk container in the recycle which is every week or twice a week!


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## dw1305 (17 Sep 2020)

Hi all, 





rebel said:


> And sobering. I feel guilty everytime I throw a milk container in the recycle which is every week or twice a week!


My guess would be that if humans survive the next couple of centuries they are going to be fairly aghast at how profligate we've been with fossil fuels, water, soil etc. 

cheers Darrel


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## Big G (17 Sep 2020)

dw1305 said:


> Hi all, My guess would be that if humans survive the next couple of centuries they are going to be fairly aghast at how profligate we've been with fossil fuels, water, soil etc.
> 
> cheers Darrel


Agree. I occasionally feel a bit guilty about all the water changing even though for me it’s no more than twenty five  litres per week across two tanks plus evaporation top ups. Not so bad in summer as it goes on plants and grass in the garden. I probably perspire,respire and pass more than that much in a given week but well, you know.

There are a few huge heffalumps in the room when it comes to our custodial role of this planet. 

I also share concerns with the OP (3d) but less on the chemistry because I think larger bodies of water must act as constant refreshment and exchange of chemicals unless its a stagnant lake (which a tank would be if we don’t do anything but top ups nor run some form of circulation I guess). It’s more about the fluctuating co2 which I have read in a few places MIGHT mitigate away from weekly large water changes in a low-tech/energy system as it could provoke algae.

However, just going on what I read as I have no skill, proof or learning to hand this on, providing there is sufficient movement at the tank surface, co2 is being exchanged all the time - inwards from air and outwards from plant photosynthesis then offgassing to produce an equilibrium of about 2-6ppm? Presumably the ’fresh’ stuff we put in  is subject to these same laws so won’t cause too much of a shift, even temporarily, to the tank‘s residual co2 levels in the round?

Bg


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## dw1305 (17 Sep 2020)

Hi all, 





Big G said:


> It’s more about the fluctuating co2 which I have read in a few places MIGHT mitigate away from weekly large water changes in a low-tech/energy system as it could provoke algae.......  providing there is sufficient movement at the tank surface, co2 is being exchanged all the time - inwards from air and outwards from plant photosynthesis then offgassing to produce an equilibrium of about 2-6ppm? Presumably the ’fresh’ stuff we put in is subject to these same laws so won’t cause too much of a shift, even temporarily, to the tank‘s residual co2 levels in the round?


We've had this discussion a <"few times on the forum">. 

I think you are right and that is partially why I like a reasonable amount of water circulation, it means that levels of dissolved oxygen and CO2 follow atmospheric levels more closely, because you have a large gas exchange surface area for diffusion to occur from.

The equilibrium value (<"at 400 ppm CO2">) is only about 0.5 ppm CO2, but <"~3 ppm is usually given as the estimated value">. 

cheers Darrel


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## Big G (17 Sep 2020)

Thanks for the links Darrel. That Krib site is going to be worth some reading. A bit like some of the older threads on here. It’s good to see how things have changed in terms of thinking and also gear. Even the last three years seems to have shifted the overton window of what passes for aesthetics, equipment and practice. Back when I was a teen with my first tank the only really heavily planted tank I ever saw was at Tachbrook Tropicals in London, Victoria (sadly now closed).

One thing that never seems to change is algae problems 

best wishes,

Bg


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## dw1305 (18 Sep 2020)

Hi all,





Big G said:


> ........I ever saw was at Tachbrook Tropicals in London, Victoria (sadly now closed).....


Unfortunately only one in an ever increasing <"horde of departed LFS">.





Big G said:


> That Krib site is going to be worth some reading.


There is a lot of good stuff on there, but all now historical.  Some of the posters are still active on <"Apistogramma forums"> and some formed <"AGA"> in the States. 





Big G said:


> A bit like some of the older threads on here


I'm biased but <"I dip in and out of UKAPS"> on <"other forums">. 

I'm not personally aware of another resource with a similar quality archive, although I would guess there are German forums, that would be equally useful, if you can read German.  





Big G said:


> .......to have shifted the overton window......


I'm going to bet that no-one has ever referenced the "overton window" before on UKAPS. 

cheers Darrel


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## Jerme (18 Sep 2020)

One thing to remember with large water changes is that you use out the soil buffering capasity much faster. Because the soil also supports water purification and houses beneficial bacteria you loose these faster as well.


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## dw1305 (21 Dec 2020)

Hi all, 


dw1305 said:


> since the end of March and I'm still using most of the milk cartons that pre-date this.


Just to say that I'm down to my last <"Pre-Covid" milk carton">, so it has lasted at least nine months. 

I was going to say "_not bad_" for something intended as a single use product, but probably "_bad for a single use product_" might be more appropriate. 

cheers Darrel


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## dw1305 (26 Dec 2020)

Hi all,
This the "last milk" carton. It is still not leaking. I had a look at the sell by date and it was June 7th, so only six months of "extra life". I've been using it to water the house plants with "Miracle Gro" (which is why it has the algae), and one or two stray snails have also found their way in  and you can see their grazing trails.





Cheers Darrel


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## Aqua360 (27 Dec 2020)

I water change based on bioload, also worth considering the difference in any water chemistry before undertaking larger changes, depending on your circumstances


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## dw1305 (20 Dec 2021)

Hi all, 


Jerme said:


> One thing to remember with large water changes is that you use out the soil buffering capasity much faster.


That is a good point, if you have hard water and an "active" substrate continual large volume water changes <"will deplete the water softening capacity of the substrate"> much more quickly.


Jerme said:


> Because the soil also supports water purification and houses beneficial bacteria you loose these faster as well.


I'm not convinced about that one. I'm really keen on an <"undisturbed substrate"> and I don't personally <"do anything like gravel vacuuming">, but I'm not convinced that water changes really have any effect what is going on in the substrate.  

cheers Darrel


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## MichaelJ (20 Dec 2021)

dw1305 said:


> Hi all,
> This the "last milk" carton. It is still not leaking. I had a look at the sell by date and it was June 7th, so only six months of "extra life". I've been using it to water the house plants with "Miracle Gro" (which is why it has the algae), and one or two stray snails have also found their way in  and you can see their grazing trails.
> 
> View attachment 159423
> Cheers Darrel


That picture is just hilarious!


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## dw1305 (28 Dec 2021)

Hi all, 


MichaelJ said:


> That picture is just hilarious!


I have a <"few of those">.  I'll take today's and post it later.

cheers Darrel


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## dw1305 (28 Dec 2021)

Hi all, 


dw1305 said:


> I'll take today's and post it later.







cheers Darrel


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## KirstyF (28 Dec 2021)

dw1305 said:


> Hi all,
> 
> 
> View attachment 178986
> ...



😂😂 This is why I need to get the lid on my tank. Cats are currently banned from the room unless I’m in it. Though now that I have my first few fish they kinda think mum bought them a new TV. 😊


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## kayjo (29 Dec 2021)

Zeus. said:


> TDS meter


Total Dissolved Solids


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## dw1305 (29 Dec 2021)

Hi all,


KirstyF said:


> This is why I need to get the lid on my tank. Cats are currently banned from the room unless I’m in it.


Probably a good idea. Unfortunately my home tanks are in the kitchen, which has a cat flap etc. <"She is a bit of a terror">, although she mainly ignores the fish now.  We've had a mouse problem this autumn because she continually brings mice in, starts meowing, drops them and they escape under the kitchen units. _Out of sight is out of mind_ so at that point she goes to try and find another one etc..

I noticed, on the uncropped photo,  that my water containers are looking a lot less green, presumably because of a combination of lower light levels and not the feeding the tomatoes etc.





cheers Darrel


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## pat1cp (29 Dec 2021)

We've had mice in the utility room too, they're a PITA. And......I'm terrified of the little beggars


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## dw1305 (29 Dec 2021)

Hi all, 


pat1cp said:


> We've had mice in the utility room too, they're a PITA


I'm lucky in that I can borrow a <"Longworth trap from work">, but I'm pretty sure that I've now caught the same <"wood mouse multiple times">. Usually when you tip them, and the hay from the trap, into the large plastic bag they burrow into the hay and hop like little Jerboas in a frantic attempt to escape, but this one just sits in the bag eating the peanut butter bait.

cheers Darrel


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## dw1305 (29 Dec 2021)

Hi all, 


dw1305 said:


> but this one just sits in the bag eating the peanut butter bait.


Here is another "tame one" from 2020.





cheers Darrel


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## MichaelJ (29 Dec 2021)

dw1305 said:


> Hi all,
> 
> Here is another "tame one" from 2020.
> 
> ...


I love this    In the late summer time we frequently have chipmunks in the garage. Unlike mice that chew on everything and can cause considerable damage, chipmunks cause no damage except they love to go through our birdseed and deer pellets.

Cheers,
Michael


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## KirstyF (1 Jan 2022)

Off topic I know but….





Barely moved for 25mins! not sure if he’s asleep sitting up or watching a snail. 😂


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## kayjo (1 Jan 2022)

I bet a lot of us look the same way...


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## jaypeecee (1 Jan 2022)

Big G said:


> That Krib site is going to be worth some reading.


Hi @Big G

I have been a fan of _The Krib_ for at least ten years. And I keep going back to it time and time again. I greatly admire the in-depth investigations that they have carried out. And, pertinent to the recent thread here on UKAPS, there is a useful section on Alkalinity vs. KH here:



			Alkalinity vs. KH
		


JPC


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## Aqua360 (1 Jan 2022)

On a side note, the only fish I have encountered that actually for whatever reason died with water changes (no matter how big, small, or matched in water values), was a rarer species of diapteron; the Latin name eludes me. Will need to dig up some info and see if I can revert back here.


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