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Article - pH is not important?

Good article. I pay next to no attention to pH. It's easy to read with cheap test kits, and it is an important secondary sign of what really matters. But hardness is the key.

In a past job, I bred close to 30 different, then often undescribed Apistogramma species. I regularly received wild caught individuals from pH 5 or so - real blackwater fish. I could breed them at pH 6.8 (the easiest pH in my then system) as long as the TDS was low.

I have a friend with strange well water that shows a pH in the high 7s, but a low tds. He's in the fish business, and I have watched wild caught Discus, a few weeks after arrival, breeding in his tanks.

pH is useful. If I have a calibrated pH meter and coastal livebearers arriving, a quick look will say whether or not I have to doctor the water. Hardwater fish do poorly or die in soft water. It's a wind that tells you a rainstorm is coming, but it's the rain that matters. Hardness is the key.

The whole concept of hard and soft water is harder to work with. The API supposed "Master Test Kits" don't even test for it, and you have to buy secondary kits or a tds/conductivity meter to get around that. You can play with pH by dumping acid or alkaline substances into the tank, but minerals have to be removed and that's more complex.
 
The whole concept of hard and soft water is harder to work with. The API supposed "Master Test Kits" don't even test for it,
I have an NTL test kit that includes tests for the KH and GH, however am I correct that the TDS is a different reading as it includes solids that the KH and GH do not?
If so is it acceptable to still use the GH to decide if water is soft or hard?
 
I'm going to bail on that question, as we have some real water chemistry expertise here. I stopped using reagent kits many years ago, and use tds for convenience. It tells me if my fish will breed, or not, in the water I'm looking at, which is my focus.
 
One post I was reading from another forum suggested that it was far more useful to use the water suppliers data rather than self testing.
 
I have long felt that the aquariumscience.org website contains some valuable information. It was that very site that long ago got me to rethink filtration with respect to the biology that develops and may mature in a filter such that routine cleaning is actually detrimental to the desired process (bacteria and microbes can colonize and develop in a matrix in the filter that enhances water purification. Cleaning all but destroys their important processing).
So with the above in mind, bio-sponge material in filters offers a much greater advantage over floss that's merely discarded. These days I let filters filled with sponge material run and run, untouched, until output flow rates are significantly reduced to nearly a trickle.

As to pH... I have long felt that often many hobbyists obsess over water chemistry and/or conditions based on the perception that they must match the conditions that any given species would see in the wild. But then again, many of our fish in the hobby are bred and raised in ponds, vats, and tanks continents away from a species origin, in a range of water chemistries. Although I'd agree that extreme ranges in chemistry is certainly detrimental, especially long term, I have to believe that there are acceptable ranges where most fish do just fine. (just my $.02).
 
As to pH... I have long felt that often many hobbyists obsess over water chemistry and/or conditions based on the perception that they must match the conditions that any given species would see in the wild. But then again, many of our fish in the hobby are bred and raised in ponds, vats, and tanks continents away from a species origin, in a range of water chemistries. Although I'd agree that extreme ranges in chemistry is certainly detrimental, especially long term, I have to believe that there are acceptable ranges where most fish do just fine. (just my $.02).
I agree 100% on filtration.

I kind of disagree on water chemistry though. There are generalist fish that do well with any water, but they aren't always the tiny fish we can keep in tanks. Small size is an evolutionary response to extreme conditions, and a few generations being commercially bred (and farms play with their water) isn't going to change a really long process of adaptation.
Keeping softwater fish in harder water works, although there are credible suggestions it may shorten their lifespans. In the wild, they would probably have been eaten before they reach those cut off points. Hardwater fish can develop neurological and kidney problems quickly in soft water.
But many of the nicest tropical freshwater fish aren't available outside specialist circles because the farms don't have the water for them.
I see breeding as the issue here, and not necessarily keeping. If you don't want either breeding behaviour to watch, or fry to raise, basic water chemistry doesn't matter. If you like rainforest fish and have hardwater, a whole range of behaviours are gone to you.
I just don't think pH is the issue. It's the easiest read parameter, so we read it. Hardness is the issue, and it matters a lot. But where pH can be bounced around with commercial products, getting soft water when your tap is hard comes with reverse osmosis, and that's a step only people really into this are prepared to take.
 
These are only my preliminary comments, as it will take me some time to read the linked article, given the numerous references in it to scientific studies, and these have to be considered to make sense of it. So I may be back later, but for now...

I concur with whomever above said GH is the most important of the parameters (aside from temperature). But it has been the pH that the hobby has been mentioning for decades; back in the 1960's the very limited "information" usually mentioned pH, but nothing was said about GH or KH. Even when I got back into the hobby in a major way in the early 1980's it was pH. I fiddled with pH, but no one ever mentioned GH as the real source issue. Like some of the other information from those days that has been proven to have been misleading if not outright false, the inaccurate myths continue notwithstanding.

No one should ever try to adjust the pH as a distinct entity; it is tied to the GH and KH, and without knowing these values and, if needed, adjusting them, attempts to change the pH will harm fish even to the point of killing them. It would be better for the hobby if all commercial pH adjusting products were removed from the shelves; not too likely to occur though, as people are making money from selling these toxic concoctions.

The pH certainly does matter, but not in the way many misbelieve. Many of us have frequently written, a stable pH even if outside the preferred range is better than a pH that fluctuates from constant attempts to make it "right."
 
I thought the read was pretty interesting, though there are a couple of items I would be a bit critical of:
1. Making assessments to the health of the fish based on 90 day studies or other short studies, I would think a longer term study would be more appropriate. For example someone, I believe it was @Byron provided a link to cardinals in high KH water in the study the fish started having kidney issues after a longer term. Some of these studies are based on conditions for shipping, vs. long term health.
2. Unfounded statements - the article is given in a somewhat scientific style yet has some unsupported comments. Example below:

"Most fish have a blood pH of 7.7 to 8.0 (Evans and Claiborne, 1997; Tzaneva et al., 2011). Logically the less the difference between the blood pH and the water pH the easier it will be on the fish. This decidedly supports the 6.5 to 8.5 range." (bolding done by me). Why is this logical? Perhaps the higher pH makes the transport and release of the oxygen to the cells easier. Perhaps a difference in pH makes other metabolic functions easier for the organism. My issue with this is it is presented as a truism but I really don't think it is, and the article doesn't provide any support for this statement. There are some other examples.

Even with the comments above, I do believe there are some truths to be had in regards to over reacting to pH. I do wonder how some aquarists end up with large pH changes. I got one of my tanks down to 5.0 once when trying to force the pH low but otherwise I have a hard time getting the pH to vary between 6.4 and 6.8.

I would love to trace a lot of the papers, unfortunately my work schedule is too busy right now.
 
Whilst roaming the web I came across this article, pH is not important , and I thought it may be of interest and discussion.
GH has been discussed and as far as I am concerned, fish should have a GH, KH & pH that is similar or the same to their natural environment. Most fishes have been around for millions of years and the Asian fish farms do try to keep the fish in water that is either soft or hard. They add salt to livebearer ponds, add limestone and bags of calcium to Rift lake cichlid ponds, and they use rain water for breeding tetras.

The article has a chart with Locality, Native pH, Acceptable pH. Under the chart they have:
"TDS needs to be above 50"
"KH and GH are not important"


I have to disagree with the article. Fish cannot survive long term in water that has the wrong pH, GH or KH for them. The article implies tetras can live in water with a pH around 8.5, and Rift Lake cichlids can live in acid water. It comments on blackwater fishes coming from water with a pH of 6.0. That's not right. Blackwater is simply tannin stained water and can have a pH ranging anywhere between 3.0 and 8.5. I have kept Salmanderfish and they come from blackwater with a pH around 4.0-5.0 and if you stick them in water with a pH around 8.0, they die pretty quickly. The way it is written also makes me think people will keep marine fish in acid water. Good luck with that. You stick a marine fish in a tank with a low pH and the fish will die very quickly. Same with African Rift Lake cichlids, they don't do well in acid water.

To get acid water you usually have to remove the GH and KH and this is bad for hardwater species like Rift Lake cichlids, livebearers like mollies, and other species. They need the minerals in the water. If you remove the minerals and drop the pH, hardwater species will suffer. We see this all the time with mollies kept in soft water with a pH below 7.0.

The article does mention Rift Lake cichlids not being able to successfully breed in acid water and softwater fishes not having good fecundity when kept in water with a high pH. That suggests the fish need a pH closer to their natural habitat.

There is a section which mentions discus being kept in highly alkaline water and those fish suffered some pretty serious issues with their blood and cortisol levels. This is related to stress. Long term, those fish would probably die much sooner than they should.

Even on this forum, members have had issues with extremely high pH killing their softwater fishes (tetras, Corydoras, etc). There was a young lady on the forum who had glolight tetras and they kept dying. Her pH was around 8.5. When she dropped the pH, the tetras started to live. There is a thread currently with rummynose tetras dying straight after they were introduced to the tank. This appears to be pH (and possibly GH & KH) related. @itiwhetu regularly mentions the wrong pH being bad for fish and increasing their risk of developing disease.

Fish are "tolerant" of a pH that is not found within their natural environment. That doesn't mean they are going to thrive in water with a pH that is completely foreign to them. It simply means humans stick the fish in an environment and they live for a bit. I doubt there are many if any scientists studying the long term molecular health issues associated with keeping fishes in water that is not natural to them. This is something that should be studied. The article does mention a short term study for blood and hormones but nothing long term.

Humans and animals can survive living on the street for a short term, that doesn't mean they thrive or will still be alive on the street in the long term. Humans and animals can live with domestic abuse short term (sometimes longer term), it doesn't mean they are thriving, and they regularly suffer long term side effects of this.

Just because something can survive under un-natural conditions, it does not mean they should be kept under those conditions.
 
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I think pH is particularly important for all new aquarists, I believe that if they keep their fish in slightly acidic tanks then many of their problems will go away. I feel that there has been a huge importance put on large water changes. Which now everyone thinks that the old stable acidic tank is outdated. So, let's concentrate on gH and kH instead, because you know that by doing large water changes your tank will never be acidic. Large water changes and Alkaline tanks will not help your fish in the long term. Almost all of the problems on this forum site are with fish being kept in Alkaline systems.
Please refer to @Colin_T post #14. His correction of this post is justified, and I agree with his statement. I am not going to plagiarize his statement. Thank you @Colin_T

Edited to add last paragraph
 
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I will add to my comment above. I personally think articles like this are dangerous to the wellbeing of thousands of fish, which will now be kept in aquariums outside of their preferred parameters.
 
I believe that if they keep their fish in slightly acidic tanks then many of their problems will go away.
@itiwhetu, add something like this to your post above. The way it's currently written makes me think all fish should be in acid water.

"I believe that if they keep fish that naturally occur in acid water, in slightly acidic tanks, then many of their problems will go away."

Acid water for fish that come from water with a pH below 7.0.

Alkaline water for fish that come from water with a pH above 7.0.
 
The belief water hardness is unimportant is good for business. Paying attention to lifespans reduces sales. If you have 9 year old cardinals, and mine die every six months, and I celebrate keeping them alive for 2 years, I'll be the buyer of fish, chemicals and gadgets. It's not an evil conspiracy, it's just forging ahead without thinking.

Most places have mineral rich water, especially in the US, the source of many postings here. So people here should just continue to steer newcomers to fish adapted to their water.

From breeding Apistogramma for years, I learned that if I could get them to spawn in 140ppm water, very few eggs hatched. The more I reduced minerals, the more eggs hatched. I could get five times as many fry at 80ppm as at 140 (my then tap level). I now see the same things with many species as a killiekeeper. Right from the get go, whether it's minerals messing with fish sperm or altering egg structure, we see the effects of water.

None of this matters to the average ornamental tanks, unless you have fish that dial down their colours in water they don't like. And if you do, you probably don't know what they look like happy. If I were cruel enough to drop a molly directly into my current very soft tap, I'd see a neurological response within minutes. But that's an extreme.

There are always myths around. The one that annoys me is the one that says our fish have been bred on farms so they've adapted. It's repeated so many times and with such authority most people accept it. It's very wishful. While I disagree with many of the rearing tricks used, the farm breeders I've spoken with are incredibly skilled people. They don't shovel future profits into unprepared ponds and hope for the best. They have systems, and they know what they are doing. For a lot of fish, that only changes once they are bagged and shipped out.
 

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