Ro Water Or Tap Water

[jimw13uk]

I would say if they have been living in RO water and are doing fine then why introduce them to untreated water. If it aint broke dont fix it

 

[Miss Wiggle]

Hi Biffer and welcome to TFF

Not wanting to slate your post as there's certainly some interesting info in there that I'd like to read more about and obviously can't make an informed comment on without doing so first, however just a couple of points I wanted to make.

It also explains why, except with a few exceptions, fish cannot move between fresh and salt water environments. In cases where this happens the fish has usually developed some means of combating the changes in salt level between the two environments.

kind of depends what you mean by 'a few exception' the amount of brackish fish that are adaptable between FW and the different salinities of SW are quite high both in the wild and in fishkeeping. There are also many examples of mainly FW fish that are quite adaptable to live in brackish or marine conditions, a lot of cichlids would be a good example. One of our regular posters Neale Monks would probably be a good person to speak to further on this as he knows a lot about brackish fish and other more adaptable fish. Of course all this could come under 'a few' as it's very flexible. But thought I'd clarify for anyone reading who didn't know.

Topping up/water changes with RO water will not take things to the extreme and buffers are usually only used where a non neutral pH is required.

Topping up and water changes are two very different kettles of fish and I think it's important not to lump them together.

taking the example of salt in the water, which as every school boy knows doesn't evaporate but the water can, so to keep saltwater at a constant salinity constant topping off should be done with RO, water changes with saltwater. I'm not sure exactly how much this applies to the 'minerals' being discussed or even exactly what they are, but I'm sure to an extent top off would be fine but water changes may not.

 

[Miss Wiggle]

we all started somewhere and took advice off friends/family which is why i started my tank on RO water because i was advised to, i was told like many of us that it takes all the harmfull stuff out the water!!
my fish have always done really well on it, so would it be advised that i start doing water changes to climatise them to normal water or keep my tank running on RO

absolutely, and I'm sorry if you feel like anyone's had a go at you, they certainly should not.

RO does take out harmfull stuff from the water but has it's disadvantages too as are being discused here.

all I can advise you to do is to follow this thread and the points being made about RO units, when it reaches a conclusion and you have a whole load of facts and opinions you need to make up your own mind about what's right for your fish and your tank.

the only lesson I would hope you learn from this is to do your own research. no one person knows everything and you have a fantastic research tool at your fingertips. Next time someone gives you some advise, get yourself on google and check it out for yourself.

IMO Research is the key to sucessful and rewarding fishkeeping.

 

[raptorrex]

<<- Raw untreated R/O water is very dangerous for all living organisms, it is so pure that it will attempt to draw salts and minerals into itself from any substance it comes into contact with until it reaches an equilibrium with them, it is also highly unstable can swing rapidly in pH from organic acids in the water. ->>


Very surprising comment. Yes water will transport across a semi permeable membrane from an area of low concentration to an area of higher concentration via the process known as osmosis. But this happens to all fish in one form or another. In a freshwater fish water passes through the skin into the fish as the salt content is higher inside the fish than in the surrounding environment. In a saltwater fish the reverse is true. Water passes from the fish into the surrounding environment as the water contents are higher than that within a fish. All healthy fish have a method of regulating the amount of water within their body … drinking/excreting. This is why freshwater fish drink minimal quantities from the environment but actually excrete large volumes of water while and marine fish will drink large quantities of water but excrete very little. This is a controlled process unless it is taken to extremes. It also explains why, except with a few exceptions, fish cannot move between fresh and salt water environments. In cases where this happens the fish has usually developed some means of combating the changes in salt level between the two environments. Topping up/water changes with RO water will not take things to the extreme and buffers are usually only used where a non neutral pH is required. As for ‘minerals’ etc. in tap water welll … hmmmmmm … that is what we are trying to strip out as most of those found in tap water are only detrimental to the live stock. Chlorine, chloroamines, nitrates, phosphates, copper, fluoride etc are not actually that beneficial (more like harmful) to water dwelling creatures.

humm, there are more things in good things in water than you seem to think. plus if water is just that H2O even a single fish poo will send the balance of the water wild. water buffering is not just for some things, it is what happens all the time.
where will the calcium that fish and inverts need going to come from? I'm not sure on fish but i know Crayfish absorb nearly all their calcium through their shells, absorbing almost nothing through their stomachs. adding it will cause massive shifts, as there is no counter balance, in the water to contain it! and that's just one thing removed by RO

CFC has a fair grip on all subjects he post on, however if you could post a single scientific paper to back up you comments? lol i tried and got 26 pages of threads confirming CFC's comments!

forgive me for "having a go" sorry its just my way.

people like CFC have long since paid there dues here. whilst there is no problem with putting you point, i feel you should back up you comments with science. whilst you post reads well, you offer no proper proof of your thoughts.

 

[Biffer2]

<<- kind of depends what you mean by 'a few exception' the amount of brackish fish that are adaptable between FW and the different salinities of SW are quite high both in the wild and in fishkeeping.->>

Brackish water fish are one of the exceptions obviously but even they usually have a preferred salinity range on one side of the scale or the other as to regards salt content. Fish migrating between full freshwater and full saltwater are extremely rare due to the different physiological processes involved.

<<- There are also many examples of mainly FW fish that are quite adaptable to live in brackish or marine conditions, a lot of cichlids would be a good example.->>

How many can perform the switch long term?

<<- Topping up and water changes are two very different kettles of fish and I think it's important not to lump them together->>
Very true but at the end of the day a water change is just a large top up procedure. A tank running at 50ppm nitrates, 50% water change (0ppm nitrates) all the water will read as 25ppm nitrates. Any ‘impurities’ in the water will only be diluted.

<<- taking the example of salt in the water, which as every school boy knows doesn't evaporate but the water can, so to keep saltwater at a constant salinity constant topping off should be done with RO, water changes with saltwater. I'm not sure exactly how much this applies to the 'minerals' being discussed or even exactly what they are, but I'm sure to an extent top off would be fine but water changes may not.->>

These days, I would guess, 50% of people with marine tanks (and the vast majority that I have come across) use RO water for water changes.

<<- plus if water is just that H2O even a single fish poo will send the balance of the water wild. water buffering is not just for some things, it is what happens all the time.-->>

Show me any fish tank, pond, lake, river with pure water in and I will give you a £100. Even water out of an RO unit isn’t pure although its purity has been improved. Adding RO water to a tank will not make it pure but anything within the water will be diluted to an extent dependent upon the size of the water change and the containments going into the water

<<- where will the calcium that fish and inverts need going to come from?->>
How much calcium do you think there is in tap water? Hence why reef keepers have calcium enriched salts and calcium additives … to help hard corals, clams and every other invert loving calcium to remain in ‘tip top’ condition.

<<- adding it will cause massive shifts->>
Why do reefkeeprs add calcium either continuously via a reactor or via additives two or three times a week then?

<<- CFC has a fair grip on all subjects he post on->>
Sorry I thought forums were a place for discussion and sharing ideas. Obviously I have come to the wrong place.

<<- whilst you post reads well, you offer no proper proof of your thoughts->> and
<<- however if you could post a single scientific paper to back up you comments->>
Pick up any basic fishkeeping book, to make double sure preferably a marine one and all will become clear.

Osmosis, dilution, fish migration etc are all basic knowledge.

 

[Miss Wiggle]

<<- kind of depends what you mean by 'a few exception' the amount of brackish fish that are adaptable between FW and the different salinities of SW are quite high both in the wild and in fishkeeping.->>

Brackish water fish are one of the exceptions obviously but even they usually have a preferred salinity range on one side of the scale or the other as to regards salt content. Fish migrating between full freshwater and full saltwater are extremely rare due to the different physiological processes involved.

<<- There are also many examples of mainly FW fish that are quite adaptable to live in brackish or marine conditions, a lot of cichlids would be a good example.->>

How many can perform the switch long term?

lots! also migration is a different issue again, there's shed loads of species that will travel from sea to an estaury or stream (therefore SW to BW or FW) to spawn and that sort of thing.

<<- Topping up and water changes are two very different kettles of fish and I think it's important not to lump them together->>
Very true but at the end of the day a water change is just a large top up procedure. A tank running at 50ppm nitrates, 50% water change (0ppm nitrates) all the water will read as 25ppm nitrates. Any ‘impurities’ in the water will only be diluted.

yes while the end result of dilution is the same, however the argument is that water changes (and although i don't think i made this clear, when i say saltwater water changes i mean RO mixed up with a commercial marine salt containing all the buffers, minerals etc) serve two purposes, not just to dilute nastie but to add back in things that get used up by the ecosystem in the tank.

<<- taking the example of salt in the water, which as every school boy knows doesn't evaporate but the water can, so to keep saltwater at a constant salinity constant topping off should be done with RO, water changes with saltwater. I'm not sure exactly how much this applies to the 'minerals' being discussed or even exactly what they are, but I'm sure to an extent top off would be fine but water changes may not.->>

These days, I would guess, 50% of people with marine tanks (and the vast majority that I have come across) use RO water for water changes.

yup, i think i've not made myself clear, I use RO for my saltwater changes, then with added marine salt containing buffers etc. Can I ask what the other 50% of people do. I don't think I know anyone who doesn't use the method described above!

<<- CFC has a fair grip on all subjects he post on->>
Sorry I thought forums were a place for discussion and sharing ideas. Obviously I have come to the wrong place.

you are absolutely right on this though, this is a place for debate and discussion. Boboboy, CFC should defend his own comments scientifically, yes he is experienced and knows a great deal but that does not mean he is not infallible or automatically correct, none of us are.

I don't mean nescessarily that Biffer is right and CFC wrong or vica versa. But we should be open to anyone who wants to come and talk with us.

Biffer I hope you haven't come to the wrong place and I hope you stay and debate with us some more!

 

[raptorrex]

i accept your comments miss wiggle. however CFC was stating things most of us already know! the onus is on the person challenging the knowledge to counter these. cant see any reason why someone should show scientific proof that cars can run on petrol. but if someone says they cant, it stands to reason they should provide proof!!

 

[Danno]

Also if you can't afford a RO unit, you can purchase 3 gallon jugs of spring water. You can purchase large amounds for very cheap. Thats what I did with all my tanks. I still treat the water with conditioners just because of peace of mind. Spring water is basically RO water with minerals there to replenish it.

 

[spud13]

thanks for everyones advice
what a debate it has come
my lfs uses RO water in all of his tanks marine and tropical, i think even the goldfishes
so i got all my advice from RO water supporters / fans
i have learned to do all my own reserch now, but as my fish have seemed happy in the RO water ive never looked into it.

 

[raptorrex]

thanks for everyones advice
what a debate it has come
my lfs uses RO water in all of his tanks marine and tropical, i think even the goldfishes
so i got all my advice from RO water supporters / fans
i have learned to do all my own reserch now, but as my fish have seemed happy in the RO water ive never looked into it.

good. keep us up to date on how you go!!!

 

[andywg]

There are many brackish fish which can live either side of the tip over point at which a fish's osmoregulatory system has to change from "freshwater mode" to "saltwater mode" (from retaining salts and passing water, to retaining water and passing salts).

Boboboy picks up a very good point on calcium. Biffer you need to stop thinking about what reefkeepers put in their tank. Almost every single supplement put into a saltwater tank is to help the invert growth, not the fish.

The below is a previous post I made on the matter of freshwater fish needing some elements and minerals:

I dug out a couple of books I have on ichtyology and both indicate that relying on food only for internal solute uptake in FW fish would not be a good idea.

Biology of Fishes, Second Edition by Carl E. Bond states that the osmotic concentration of typical freshwater fish blood is in the range of 265 to 325 mOsm kg-1, marine bony fish maintain a level of around 380 to 470 mOsm kg-1 with Sea water being 800 to 1,200 mOsm kg-1. I am having trouble gaining an osmotic concentration for any freshwater streams, though it appears to be in the region of 1-10 and would expect RO water to be 0.

Fishes: An Introduction to Ichtyology, Fifth Edition by Peter B. Moyle and Joseph J. Cech Jr talks about how freshwater fish operate hyperosmotically and cites the research of Grizzle et al. 1985 which showed that diffusional losses of monovalent ions (e.g., across the gill membranes) are reduced in external environments having higher calcium concnetrations.

This book continues to discuss how lost internal solutes are replaced by those taken in with food or taken up at the gills, noting the work of Laurent et al. 1985 that in especially ion-deficient mountain water chloride cells are well developed on gill lamellae as well as filaments indicating that enough of the necessary internal solutes of freshwater fish are replaced via the gills to require improvemets to that capacity for a fish to succeed in an environment of low solution.

The book then describes the exact method of freshwater osmoregulation based on the beta chloride cells occuring on gill filaments between and occasionally on lamellae (Pisam et al. 1987). Through the reactions at this cells the fish maintain their internal level of sodium and chloride. This same reaction is believed the most probable uptake of calcium by freshwater teleosts.

All of the above shows how freshwater fish depend on some (albeit a comparatively low) level of solutes in the water to effectively osmoregulate. The absence of these solutes by keeping a fish in pure RO water will place unnecessary strain on the fishes' osmoregulation as it constantly tries to combat an increased rate of loss of internal solutes as well as living in water devoid of the natural level of solutes from which it replaced many of them.

The buffering element has been pointed out. Pure RO water can be very unstable. The lack of buffering means that it is very conceivable that a small problem (such as some trapped food rotting) causes a very large swing in pH.

 

[CFC]

I lack the scientific words to explain exactly how pure R/O water affects freshwater fish so i am going to leave it to someone more qualified on the subject and will PM Bignose and ask him to explain in this thread once again.

 

[Fella]

Regardless of the science though, I've seen countless times more experienced fishkeepers than myself saying that plain RO is very dangerous to use for fish, and that additives should be used.

The experience of that alone is enough for me.

 

[raptorrex]

Regardless of the science though, I've seen countless times more experienced fishkeepers than myself saying that plain RO is very dangerous to use for fish, and that additives should be used.

The experience of that alone is enough for me.

could not have said it better myself!!!

 

[andywg]

Regardless of the science though, I've seen countless times more experienced fishkeepers than myself saying that plain RO is very dangerous to use for fish, and that additives should be used.

The experience of that alone is enough for me.

could not have said it better myself!!!

While part of me agrees with this, part of me is wary.

Without the science to back it up and just going on experts you can end up in interesting places. 20 or so years ago, many experts would tell you that aquarium salt and old water was the way to a good tank, just make sure you have an under gravel filter.

I would far rather look at the science underpinning it.

The basics of it is, by using pure RO, you are placing an extra strain on the fish to osmoregulate and putting it in an entirely unnatural set of water parameters. On top of this you have a water with very little buffering capability which can lead to big problems.

That is not to say that doing so will always lead to problems, just that you going to some effort to make things worse for your fish. Do you really want to do that?