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RO unit worth it?

Obviously, if you’re trying to breed soft water species it’s important, but otherwise not so much.
There is no way I would keep Dwarf Cichlids from the Amazon Basin at the same water parameters (including water hardness) I used to keep African Rift Lake Cichlids ... That said, most fish, especially fish bred in captivity, have a far higher tolerance to a much wider range of water parameters than most tend to believe. That said, I don't think its distraction from the hobby of fish keeping to at least be in the ballpark of the water parameters found in the fishes natural habitat - and see no reason why the fish would not be better off with that.

Cheers,
Michael
 
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There is no way I would keep Dwarf Cichlids from the Amazon Basin at the same water parameters (including water hardness) I used to keep African Rift Lake Cichlids ... That said, most fish, especially fish bred in captivity, have a far higher tolerance to a much wide ranger of water parameters than most tend to believe. That said, I don't think its distraction from the hobby of fish keeping to at least be in the ballpark of the water parameters found in the fishes natural habitat - and see no reason why the fish would not be better off with that.

Cheers,
Michael

I missed that in my post, hobby bred, or fish farm bred tend to be a lot more tolerant 👍
 
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I don’t know where I sit on the idea that (captive bred) fish need the right kind of water. I’ve killed a number of fish prematurely and I can’t help but wonder if it’s because of the water parameters. Though I do suspect that they were underfed, as I took the advice that the fastest way to kill fish was to overfeed them a little too seriously. Then again I’ve unintentionally bred poropanchax normani in rock hard water, so I’m really not sure.

At the end of the day I think I’ll probably start using RO or rainwater in the future when I start to keep tetras and cichlids (some wild caught). I just don’t think I would feel comfortable providing them with suboptimal conditions. There’s also the inconvenience of salt creep, but as far as plants are concerned, it doesn’t matter.
 
For sure, if we’re talking extremes and particular species with exacting requirements you’re very probably right. But that’s not what I was getting at and I don’t think that is within the experience of the average hobbyist.

It could also be that we are attributing cause and effect wrongly. I’ve had plenty of wild caught soft water fish live beyond what is deemed to be their natural lifespan in hard water, and happily without apparent stress. Water quality is probably of equal or greater importance. Perhaps there are other confounding factors we’re not necessarily aware of.

And something else that has always puzzled me... How come captive bred so called soft water fish are thought to be more tolerant of varying water quality, hard or otherwise? Do their genetics suddenly and drastically change simply because they are bred in hard water, for instance? I very much doubt it; that's dangerously close to Lamarckian evolution.

Fish are probably more adaptive to different environmental conditions than is perhaps commonly thought. Many aquatic habitats are subject to a range of hydrological conditions from flood to drought during wet and dry seasons for instance. The species that live in them in turn experience a range of chemical and thermal changes. But of course South American dwarf cichlids ain’t going to be happy kept in the same conditions as African Rift Valley cichlids and vice versa.

Also spawning doesn't necessarily indicate optimal water conditions, just as lack of spawning indicates sub-optimal conditions. Rather certain changes in water parameters will trigger spawning. Changes which fish associate with conditions likely to give their offspring the greatest chance of survival. For instance, many tetras breed during the rainy season.
 
And something else that has always puzzled me... How come captive bred so called soft water fish are thought to be more tolerant of varying water quality, hard or otherwise? Do their genetics suddenly and drastically change simply because they are bred in hard water, for instance? I very much doubt it; that's dangerously close to Lamarckian evolution.
I do not know the answer, and it probably depends on the species of fish as well, but I suspect it might have to do with the selection process over time of the specimens breed in captivity that gets to dominate the breeding stocks, trade and eventually ends up at the LFS - as opposed to much slower natural (Darwinian) selection… Unfortunately, there is also a lot of inbreeding taking place which tend to impede biological fitness so that somewhat goes against the idea that fish bred in captivity should be hardier.

Fish are probably more adaptive to different environmental conditions than is perhaps commonly thought. Many aquatic habitats are subject to a range of hydraulic conditions from flood to drought during wet and dry seasons for instance. The species that live in them in turn experience a range of chemical and thermal changes.
That is my belief as well.

Cheers,
Michael
 
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Sorry I didn’t respond to this sooner; my response required a little more thought and also a keyboard on that iPad isn’t something I enjoy typing on.

I am unable to explain it; but I have seen it - some fish with minor adjustments to water params will effectively become okay over time in water they’re not particularly preferring. Now these fish aren’t extreme requiring fish, I mean wild guppy coming in with a request for super high gH then for their many times removed offspring to be fine in pond water! Imagine how many discus died to get that new strain that is alright in hard-ish water?! I'm saying, it certainly is possible to breed in some tolerance - but I can't explain it.

Fish died in my water as a kid for years, until I started using collected water (from a stream, pond, and gutter - I know!).

 I mentioned in an earlier post “extremes” as it protects me somewhat from having to make lots of justification and references as extremes are fairly well documented. Intolerances of fish which are closer either side of the mid point w/neutral pH is a bit harder to prove - as in I cannot.
 
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I am unable to explain it; but I have seen it - some fish with minor adjustments to water params will effectively become okay over time in water they’re not particularly preferring. Now these fish aren’t extreme requiring fish, I mean wild guppy coming in with a request for super high gH then for their many times removed offspring to be fine in pond water! Imagine how many discus died to get that new strain that is alright in hard-ish water?! I'm saying, it certainly is possible to breed in some tolerance - but I can't explain it.

Fish died in my water as a kid for years, until I started using collected water (from a stream, pond, and gutter - I know!).

 I mentioned in an earlier post “extremes” as it protects me somewhat from having to make lots of justification and references as extremes are fairly well documented. Intolerances of fish which are closer either side of the mid point w/neutral pH is a bit harder to prove - as in I cannot.
I agree with Tim. How does anyone know what a fish died of? Are autopsies performed to determine cause of death? Can anyone pin the cause directly to Calcium/Magnesium concentration in the water? Also, what is the mechanism of the damage done?
People assess blame based on their favorite boogieman. From EPA and other environmental agency studies we know the #1 killer of fish historically is hypoxia due to water pollution. We also know that folks often refuse to change the water in their tanks for reasons of "keeping parameters the same" which is another myth. Can the two be related? I reckon so. I don't have any trouble keeping fish alive long term in hard water, whether it be discus or dwarf chiclids. There are as many ways to kill fish as there are the number of hobbyists out there, and as mentioned, fish have a wide range of adaptability. Pet shops stayed in business for years on end specifically because hobbyists could not keep their fish alive for a multitude of reasons, mostly overcrowding, overfeeding and the resultant foul water.
Hobbyists assume that just because they have a filter then that automatically means their water is clean, but this isn't true. Unremoved waste continues to damage the inhabitants. People really need to focus on cleanliness instead of on "water parameters".

Cheers,
 
Hey, @ceg4048 of course we cannot be certain of what is killing a fish. I’m posting to make note that soft/hard water fish can slowly die when they’re not in water that matches what they prefer. Of course they adapt, some better than others.

Because I cannot prove (scientifically) any of this, I’m just going by experience. I agree with a lot of what you’re posting, but can we not disregard water hardness as a cause of fish deaths?
 
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Hobbyists assume that just because they have a filter then that automatically means their water is clean,
Not only an assumption, but there's also a huge amount of marketing aimed at selling us ever more expensive and complicated filters.
 
All l can add is the chap l know with the Discus fish house used RO water although he did have water butts scattered about. Most tanks had what looked like German Discus feature tank had a dozen or so Wild Discus so l suppose he wasnt going to rely on the utility companys with a few thousand pounds of fish .
 
My water is GH12 / KH5 and I ended up with an RO unit as I was buying distilled water to drop the hardness slightly for the shrimp I keep.
Concerned about waste etc, I got a pumped model which should of cost about £140. As the seller was absolutely useless Amazon ended up refunding me.
This unit seems to waste about 50% (so it takes 20l of tap water to make 10l of RO) which isn't too bad.

I have never got around to using it in my main tank and to be honest I doubt I ever will as it would be a right faff to produce the RO and use this to change 90l of water.
In the shrimp tank I use 1/3rd RO and 2/3 tap which drops the GH to about 8 and I top up any evaporation with RO. I know RCS should be fine in GH12 water but after loosing two colonies to what appeared to be molting issues I think the fact they were probably bred for many generations in remineralised RO means they are not as hardy as they used to be (and the one thing I have found is that they do not like big changes at all).

I would only consider buying one if your livestock dictates it (Wild fish, delicate shrimp, things like Chocolate Gourami...)
I have plants growing like crazy in my water and the only thing I cannot seem to get to thrive is Java Fern and Amazon Swords (which should both be very hardy and fine in hard water....) whether this is related to the hardness or not I can't say but I have essentially just given up on these two plants and found plenty which are doing great.
 
Here still thinking if i should/want to use and buy a RO unit.
Currently using rain water as a test to see if it works good(just for the plants etc).
Also running CO2, plant ferts, high light etc.
What i noticed was that plants like rotala green did better compared like before.

Tap water here has (via water company site):
dH: 8,67 - 10,71
pH: 7,75 - 7,89

So for now, yes it works great but i am depending on the weather/rain. Also it works because, well, we had more rain compared to the last 3 years :p
But during the summer.......... The rain barrel will be more empty than full i am afraid.
Also using a 200L barrel on the attic which i have filled with rain water for use now (great fun to get it to the attic with jerrycans.......).
But also as a test to see if i will get/use a RO unit (which will be located on the attic) how it will work with a hose/tube back to the aquarium 2 floors down.
This test works. Simple 15/18 (more flexible) tube with a eheim tap on the end. gravity will do the rest.

Downside with use of a RO unit will be the water waste (and extra security needs to build in to prevent overflows etc. Dont want a 2 floor waterfall in my house..... )
So i am still doubting if i really need it for a high tech aquarium (current aquarium will soon be replaced/upgraded with an ADA 120P)
Looking at the aquariums like green aqua etc is using with TDS ratings around 120ppm is nice. But still........ Do i need to through away "waste water" for this...........
 
Hello,
Not speaking of breeding (which is a whole different matter for many speices), there seem to be enough testimonials based on practical experience to at least make it plausible to suggest that fish that are naturally adapted to soft water will do better in soft(er) water rather than hard(er) water and vise-versa. And personally I do believe in that, but where is the scientific evidence either way? What are the limits and consequences in terms of metabolism/growth, coloration, physical / psychological stress, life expectancy, susceptibility to illnesses, mortality rate over time etc.? Can my Cardinals or Rams be just as happy along those metrics at 25 KH/GH as they are at the current 5-6 KH/GH (assuming maintenance is impeccable in both cases) ? I doubt it, but I do listen when experts tell me otherwise.
Did anyone conduct scientific studies on this particular topic? Considering the size of the ornamental fish trade and the number of people involved in this, I would think so, but I haven't been able to find any studies that just looked at water hardness in isolation. I think it's rather consequential considering how much time and money hobbyists spend on potions and gadgetry to reach that certain KH/GH and of course the well-being of our fish.

Cheers,
Michael
 
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Hello,

Did anyone conduct scientific studies on this particular topic? Considering the size of the ornamental fish trade and the number of people involved in this, I would think so, but I haven't been able to find any studies that just looked at water hardness in isolation. I think it's rather consequential considering how much time and money hobbyists spend on potions and gadgetry to reach that certain KH/GH and of course the well-being of our fish.

Cheers,
Michael

You'll be hard-pressed to find a good scientific study on this or much else hobby related really.

While fish keeping is a popular hobby, studies etc cost money which just isn't there or just the fact that's it not all that important. Most of the scientific research in this sort of area takes place in commercial aquaculture and occasionally benefits us.
 
You'll be hard-pressed to find a good scientific study on this or much else hobby related really.

While fish keeping is a popular hobby, studies etc cost money which just isn't there or just the fact that's it not all that important. Most of the scientific research in this sort of area takes place in commercial aquaculture and occasionally benefits us.
@Nick potts True. Pretty much all the literature I have been able to dig up on online science journals are related to commercial fish farming for food production.
 
@Tim Harrison Thanks for the link.

EDIT: I wish there would be a pop-up book version of this paper. I am pretty well versed in math and science in general being a computational imaging expert, but this is just too much jargon, biology and (organic) chemistry for me to grasp. I hope someone with a mind for this will read it and laymanize the conclusions pertaining to our discussion on water hardness.

Cheers,
Michael
 
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The paper in itself is fairly tangential to what we're discussing. I just thought osmoregulation etc in fish living in aquatic environments with increasing ion concentration might be a line of enquiry that would yield some results that were perhaps more relevant.

I think the paper is explaining how different taxa have similar physiological ways of coping with increasing salinity and ion concentration. Although the mechanisms aren't completely understood and neither are the toxic effects of certain anthropogenic ions not usually found in the corresponding aquatic habitats in such high concentrations.

But that was back in 2016, so there maybe recent papers that have a more definitive answer. Although they may also be somewhat tangential to our discussion we might be able to draw some relevant inferences from them.
 
I know a lot has been said but I just thought it might be useful to add my experience here. I changed from hard London tap water to RO and there was a marked improvement in fish health - no more unexplained deaths basically. I love soft water fish so it made sense for me. Plant wise I think better in tap - I’ve just switched a new tank over to RO from tap and the plants aren’t growing so well now.
 
I know a lot has been said but I just thought it might be useful to add my experience here. I changed from hard London tap water to RO and there was a marked improvement in fish health - no more unexplained deaths basically. I love soft water fish so it made sense for me.
I agree wholeheartedly! I've had the same experience, but I wish there would be hard science and not just anecdotal evidence such as my own and yours (and many others) to back or contradict this.
 
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