Whatis the is the hardness supposed to be for a livebearer comunnity tank

El chapo

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Tank also houses black Khali loache/otos/bristlenose pleco/ghost shrimp/mystery snail and corydoras.
 

Sgooosh

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lots of those are soft water...
i dont know but ill go for the middle maybe 7.4?
 

Byron

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There is no real middle ground with respect to soft water and hard water fish species, but there is some overlap, depending upon the species.

The pH was mentioned in the above post, this is secondary. Primary issue is the GH, the general or total hardness which is a measure of the dissolved calcium and magnesium in water. For fish requiring hard water, this is crucial because the functioning of the physiology of the fish depends upon the calcium (especially) in the water. Water is continually entering freshwater fish via osmosis, through every cell, and the dissolved calcium (like any dissolved mineral, and many other substances) is able to diffuse across the cell membrane, thus entering the fish's bloodstream and internal organs. This calcium must be in the water; fish cannot acquire sufficient calcium from their food no matter what they eat, and of course some livebearers such as mollies are largely herbivorous. Without moderately hard or harder water, the fish slowly weaken, are stressed, and will either succumb to issues they should normally be able to easily deal with, or simply not live a normal lifespan.

Soft water fish are much the opposite; the calcium in the water again enters the fish, but this time the physiology of species that have evolved to function in soft water causes the calcium to be pulled into the kidneys, but in most cases it slowly blocks the kidney tubes, and the fish again just dies, with absolutely no external symptom. Soft water species are therefore going to have a better life in softer rather than harder water. Different species have differing levels they can tolerate.

The pH is usually relevant to the GH; where the GH and KH are high, as they will be in "hard" water, the pH will be basic and thus suited to the fish species. Where the GH and KH are low, as in soft water, the pH will tend to be on the acidic side. Other factors play into this, like CO2, but this generality is just that, general.

Livebearers should be kept in water with a GH no lower than 10 dH but some, especially mollies, should never have it below 12 dH. These are absolute minimums, it is always better to have the GH higher, up to 30 dH is fine. When soft water species are also in the tank, one obviously has to be careful not to go so high they begin to suffer. The non-livebearer fish mentioned in post #1 are soft water species, and I personally would not combine them with livebearers simply because I would be able to increase the GH (if needed, depending upon the source water) to better suit the livebearers so they will be healthier. Some Corydoras species will manage in moderately hard water. As I expect it will be asked, the GH should not be higher than 20 dH, but I would never keep any cory species that high. It is simply not kind to the fish.
 

Sgooosh

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There is no real middle ground with respect to soft water and hard water fish species, but there is some overlap, depending upon the species.

The pH was mentioned in the above post, this is secondary. Primary issue is the GH, the general or total hardness which is a measure of the dissolved calcium and magnesium in water. For fish requiring hard water, this is crucial because the functioning of the physiology of the fish depends upon the calcium (especially) in the water. Water is continually entering freshwater fish via osmosis, through every cell, and the dissolved calcium (like any dissolved mineral, and many other substances) is able to diffuse across the cell membrane, thus entering the fish's bloodstream and internal organs. This calcium must be in the water; fish cannot acquire sufficient calcium from their food no matter what they eat, and of course some livebearers such as mollies are largely herbivorous. Without moderately hard or harder water, the fish slowly weaken, are stressed, and will either succumb to issues they should normally be able to easily deal with, or simply not live a normal lifespan.

Soft water fish are much the opposite; the calcium in the water again enters the fish, but this time the physiology of species that have evolved to function in soft water causes the calcium to be pulled into the kidneys, but in most cases it slowly blocks the kidney tubes, and the fish again just dies, with absolutely no external symptom. Soft water species are therefore going to have a better life in softer rather than harder water. Different species have differing levels they can tolerate.

The pH is usually relevant to the GH; where the GH and KH are high, as they will be in "hard" water, the pH will be basic and thus suited to the fish species. Where the GH and KH are low, as in soft water, the pH will tend to be on the acidic side. Other factors play into this, like CO2, but this generality is just that, general.

Livebearers should be kept in water with a GH no lower than 10 dH but some, especially mollies, should never have it below 12 dH. These are absolute minimums, it is always better to have the GH higher, up to 30 dH is fine. When soft water species are also in the tank, one obviously has to be careful not to go so high they begin to suffer. The non-livebearer fish mentioned in post #1 are soft water species, and I personally would not combine them with livebearers simply because I would be able to increase the GH (if needed, depending upon the source water) to better suit the livebearers so they will be healthier. Some Corydoras species will manage in moderately hard water. As I expect it will be asked, the GH should not be higher than 20 dH, but I would never keep any cory species that high. It is simply not kind to the fish.
idk if this is wrong but i raised guppies in our neutral water for generations and generations.
they live with cories and are very happy
i guess it worked out?
 

Byron

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idk if this is wrong but i raised guppies in our neutral water for generations and generations.
they live with cories and are very happy
i guess it worked out?

Guppies are a bit different. I happened to acquire a female by accident (store person got her in the bag without noticing) and not having hard water tanks, I put the guppy in the QT. It lived for months, to my surprise, but I certainly would not want to vouch for her condition.
 

Essjay

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i raised guppies in our neutral water for generations and generations.
Can I ask, what do you mean by 'neutral'?

Neutral usually refers to pH, meaning 7.0 or perhaps a point in either direction.
With hardness, we usually say hard soft or somewhere in the middle.
 

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