Water softeners and aquarium

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maritzsa

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Hey guys, I have been doing research on whether water softener systems in houses is safe for fish keeping. My original water in my area is well water with GH and Kh up in the areas of 15-18 (dgh and dkh) and the ph at 8.2. My family installed a water softener system (works with water crystals, i believe either sodium or potassium based) as getting rid of the calcium in the water is beneficial to all machinery that works with water as well as introducing other benefits that I don't exactly understand. After the softener was installed my water parameters were, 1-3 for GH, 15 for KH and 8.2 pH. So only the GH was reduced to very soft. As of right now I don't think there is an external faucet or any faucet that will be disconnected from the softener system to release the original well water. I have been keeping and bred bettas as well as zebra danios fine, as well as plants but I am afraid the softener system actually hurts the living things in long term. What do you guys think? If I do find a faucet that has access to water that doesn't pass through the softener system, should I use that for my fish keeping purposes from now on (which has high calcium and magnesium content)?
 
In an article I wrote on total dissolved solids, I cited the following:

Water Softeners [cited verbatim from Dr. Neale Monks]

“Domestic water softeners do not produce soft water in the sense that aquarists mean. What domestic water softeners do is remove the temporary hardness (such as carbonates) that potentially furs up pipes and heaters by replacing it with permanent hardness (such as chlorides) that does not. While you can pass this softened water through a reverse-osmosis filter to remove the permanent hardness as well, until you have done so, you shouldn't consider the softened water as being suitable for soft water fish.

In fact, aquarists are divided on whether the resulting softened water is safe for keeping fish at all. The odd balance of minerals in softened water is not typical of any of the environments from which tropical fish are collected. While the chloride levels are much higher than those soft water fish are adapted to, the levels of carbonate hardness are too low for the health of hard water fishes like Rift Valley cichlids, goldfish, and livebearers. So the safe approach is not to use it in any aquarium, and instead draw water from the unsoftened drinking water source in the kitchen.”

Monks, Neale, “A Practical Approach to Freshwater Aquarium Water Chemistry,” Wet Web Media.
 
In an article I wrote on total dissolved solids, I cited the following:

Water Softeners [cited verbatim from Dr. Neale Monks]

“Domestic water softeners do not produce soft water in the sense that aquarists mean. What domestic water softeners do is remove the temporary hardness (such as carbonates) that potentially furs up pipes and heaters by replacing it with permanent hardness (such as chlorides) that does not. While you can pass this softened water through a reverse-osmosis filter to remove the permanent hardness as well, until you have done so, you shouldn't consider the softened water as being suitable for soft water fish.

In fact, aquarists are divided on whether the resulting softened water is safe for keeping fish at all. The odd balance of minerals in softened water is not typical of any of the environments from which tropical fish are collected. While the chloride levels are much higher than those soft water fish are adapted to, the levels of carbonate hardness are too low for the health of hard water fishes like Rift Valley cichlids, goldfish, and livebearers. So the safe approach is not to use it in any aquarium, and instead draw water from the unsoftened drinking water source in the kitchen.”

Monks, Neale, “A Practical Approach to Freshwater Aquarium Water Chemistry,” Wet Web Media.
So, just to be sure, if I do have one faucet that is not connected to the softener I should just switch to using that for my fishkeeping needs right?
 
So, just to be sure, if I do have one faucet that is not connected to the softener I should just switch to using that for my fishkeeping needs right?

This would avoid the salt, sodium chloride, if that is what the softener adds. That means the water would be fairly hard, as you've noted previously. Some fish need this, some do not. Hard water species are all the livebearers, rift lake cichlids, some of the rainbowfishes. There are also some species that are basically softer water species but could probably manage here, thinking of some of the barbs and danios and some others.

Another option is to dilute the water with "pure" water to reduce the GH/KH/ph for species preferring softer water. This is another issue entirely, but one that comes up on the forum regularly, there have been two or three threads just this past week or so.
 
This would avoid the salt, sodium chloride, if that is what the softener adds. That means the water would be fairly hard, as you've noted previously. Some fish need this, some do not. Hard water species are all the livebearers, rift lake cichlids, some of the rainbowfishes. There are also some species that are basically softer water species but could probably manage here, thinking of some of the barbs and danios and some others.

Another option is to dilute the water with "pure" water to reduce the GH/KH/ph for species preferring softer water. This is another issue entirely, but one that comes up on the forum regularly, there have been two or three threads just this past week or so.
Yes the softener is salt based either Sodium or Potassium. I mean other than the lack of calcium and magnesium do these salts actually have any harm to animals and plants? If not I already keep danios and bettas which are, to my understanding, low GH fish. And I already dose ferts that also provide plants with calcium and magnesium and other trace minerals.
On another note, I also have cherry shrimp and they breed but I think perhaps using the non softened hard GH water will be more beneficial for them, so maybe just for their tank I use unsoftened hard water.
 
Yes the softener is salt based either Sodium or Potassium. I mean other than the lack of calcium and magnesium do these salts actually have any harm to animals and plants? If not I already keep danios and bettas which are, to my understanding, low GH fish. And I already dose ferts that also provide plants with calcium and magnesium and other trace minerals.
On another note, I also have cherry shrimp and they breed but I think perhaps using the non softened hard GH water will be more beneficial for them, so maybe just for their tank I use unsoftened hard water.

These are two very different issues, the salt and the hard minerals. GH measures only the latter, primarily calcium and magnesium. Salt does not affect GH.

The use of salt (sodium chloride) in a freshwater aquarium is detrimental to all fish, to varying degrees; soft water species have much greater problems than fish from hard waters, but they too are impacted. You can read the reasons in my article on salt here:

The GH is a totally different issue, involving dissolved calcium and magnesium primarily. Freshwater fish continually take in water via osmosis through their cells (the fish equivalent of drinking water) and substances dissolved in the water that are able to diffuse across the cell membrane, which minerals do, are removed by the fish from the water. The hard water species I mentioned in my previous post absolutely need these minerals in the water in order to have a good functioning of their physiology. By contrast, soft water species do not need these minerals, and when their kidneys remove them, they will in time block the kidneys, killing the fish. This can occur more rapidly depending upon the species and the level of minerals involved.

As for plants, salt will dehydrate them, again depending upon the levels and the plant species, as some are more tolerant than others--Java Fern for example is said to do well in brackish water, but delicate plants would not last long in such water. As for the hard minerals, plants obviously need calcium and magnesium (these are two macro-nutrients required by aquatic plants) but not in large quantity--a GH of 3 or 4 dH will provide all the calcium and magnesium for the plants, but this low amount would be totally insufficient for hard water fish by comparison. And the level of minerals in most plant fertilizers will be so minimal as to not be an issue for fish. I've used comprehensive liquid fertilizer for years, and substrate tabs, and I have never seen an increase in GH which in my tanks is at zero (very soft source water).

Shrimp I will leave to the members with more knowledge, as I've never kept them. Most of them need the calcium for their exoskeleton, though I believe there are some soft water species/varieties. Others will know.
 
Yes the softener is salt based either Sodium or Potassium. I mean other than the lack of calcium and magnesium do these salts actually have any harm to animals and plants?
Long term exposure to high or unnatural levels of sodium or potassium can damage the kidneys of any animal, bird or fish. Long term exposure for fish is more than 4 weeks.

A reverse osmosis (R/O) unit would allow you to remove most of the minerals and then you could use that water or a mixture of R/O water and well water for your fish, and not worry about them suffering from health issues associated with the sodium or potassium.
 
Long term exposure to high or unnatural levels of sodium or potassium can damage the kidneys of any animal, bird or fish. Long term exposure for fish is more than 4 weeks.

A reverse osmosis (R/O) unit would allow you to remove most of the minerals and then you could use that water or a mixture of R/O water and well water for your fish, and not worry about them suffering from health issues associated with the sodium or potassium.
I have been keeping 30-40 bettas and danios adults and babies for 6-7months with the softener. So perhaps the system does contaminate the water so much
 

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