Water options?

The Big Figfetti

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I don’t know why I haven’t asked this before now. I assumed it was a no go, and I went with what I used to do.

But…..
Can I use my water softener water for my tanks? I have very hard water here in south Texas. We have a water softener that we use in the house. And we have a small RO system for drinking water at the sink. That one goes through the softener and then through the RO.
I skipped using those two options, and just used the regular tap water from outside, because that’s what we water the grass with. I assumed that was my only option.

My current process is holding a tank with 1/2 tap water and 1/2 RODI water from the LFS, then using that water for water changes. And of course conditioning it when added.

I would love to just use water from the house, if it’s possible to use water softener water. Because I can have this on temperature control when adding water to the tank, and wouldn’t have to hold water in another holding container.
What do I need to test for and look out for when going this route? They told us not to water the grass with this water, and not to water our plants with it inside.

Anyone able to explain this to me, and what I should be looking for? Is this possible?
 
It depends how the softener works. If it is one that replaces the hard mineral salts (calcium, magnesium) with sodium salts, it is just as bad for soft water fish.

Neale Monks has this to say:

“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.”​

Obviously the GH/KH of your unsoftened water is also a factor.

Then there is the fish species. Some soft water species can manage in harder water while others cannot.
 
It depends how the softener works. If it is one that replaces the hard mineral salts (calcium, magnesium) with sodium salts, it is just as bad for soft water fish.

Neale Monks has this to say:

“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.”​

Obviously the GH/KH of your unsoftened water is also a factor.

Then there is the fish species. Some soft water species can manage in harder water while others cannot.
I would have to contact the company to figure all that out.
Sounds like it’sa no go though, and I’m not sure I would want to ’experiment’ either.
Thanks, I appreciate the feedback.

Is there a way to add a device to the outside tap, to make it temp controlled? I’m sure that’s a dumb question.
 
The water that goes through the RO system is fine - but unless you have very soft water fish you will need to re-mineralise.
 
“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.
This is not quite correct. Salt water softeners (which dominate the market) have resinthat is charged with NaCL When hardware comes in contact with the resin. the resin and sodium chloride reacts with the Calcium (Ca) and magnesium (Mg) carbonate in the water. The Ca Mg, and CL stay in the resin and water softener. The Softened water Then has little to no Ca and Mg. in stead the softened water is now loaded with Sodium bicarbonate.

Later the Resin is mixed thea concentrated NaCL solution. The resin they releases the Ca Mg Chloride into the brine and the resin absorbs sodium Chloride. The Mg, Ca Chloride is flushed down the drain. Calcium and magnesium chloride never gets to the aquarium.


All animals require a balance of Ca, Mg, Na, and K (potassium to live) Normal tap always has some Ca, Mg, Na, K. So most tap water is in balance. However softened water has zero Ca, Mg, and Excessive Na and lvery little K. Softened water is out of balance and this can kill a fish.

Mixing RO water with regular tap water is the best solution. Your Sink RO system can produce enough RO for your tank but it just needs time to produce enough. Most in sink systems produce about 25 gallons per day. So after 4 days you could get a 100 gallons of RO water. There are RO systems that can produce 100 to 50 gallon per day (This is one).

If you don't have GH, KH, and PH test kits get them. GH (general hardness) only detects calcium and magnesium. KH only detects carbonates. Carbonates also affect PH. Use these test to monitor the levels in your aquarium Tap water can very seasonally So use the GH, KH, PH test to insure your tank water stays stable.
 
Note softened water doesn't have enough of anything to satisfy the humans boddy's mineral needs. People 95% of the minerals they need from food not water. So it is safe for you to drink softened water unless your doctor identifies a medical condition that could be impacted by the high sodium content of the softened water. Mineral imbalances in the human body can kill people but it is hard to do by just drinking water. But it does happen.
 
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I did all the tests and here is the tanks parameters. This is using my outside regular tap water. Not filtered.
These tests are after a 50% water change 48 hours ago. It’s been sitting for 2 days.
This is a fully planted tank. No inhabitants yet. (Still waiting for more plants and a full cycle).


pH 7.4
GH 10 drops - 100-200
KH 9 drops - 100-200
Calcium 80
Temp - 80
Ammonia - 0
Nitrite - 0
Nitrate - 0

The purpose of this thread was because I assume that my water is too hard. But after doing the tests, I’m wondering if this is acceptable for most plants, fish, and inverts.
 
Hardness doesn't really mater for plants. 1 degree of hardness should be enough as long as cCa and Mg are pressent. ince you don't know Mg levels a going a little little harder (3 degrees) would be oK. 10 degree is OK. wants need Ca and Magnesium (which you hav, and 12 other nutrients plants need. Plants do like the water to be a little acidic Manyof the trace nutrients plants need dissolve better in acidic water with No KH. But fish waist is also fertilizers the fish will periodically add nutrients. How many fish are required is impossible to predict. Any plant problems you might have would likely be due to the a shortage of any one of the remaining 12 nutrient.

I have no experience with hard water so I don't know which fish will or inverts will do best wit oudo well with your tap water
 
Hardness doesn't really mater for plants. 1 degree of hardness should be enough as long as cCa and Mg are pressent. ince you don't know Mg levels a going a little little harder (3 degrees) would be oK. 10 degree is OK. wants need Ca and Magnesium (which you hav, and 12 other nutrients plants need. Plants do like the water to be a little acidic Manyof the trace nutrients plants need dissolve better in acidic water with No KH. But fish waist is also fertilizers the fish will periodically add nutrients. How many fish are required is impossible to predict. Any plant problems you might have would likely be due to the a shortage of any one of the remaining 12 nutrient.

I have no experience with hard water so I don't know which fish will or inverts will do best wit oudo well with your tap water
Thank you! I don’t have any plants right now. Just dosing right now with water changes.
 
As Steven noted there is no issue for plants here. And I believe we are in agreement that the water used for the tank(s) should not be coming out of the filter/softener but pre-filter/softener.

So that leaves the GH at 10 dH if your test was accurate. I am assuming the API test or similar where 1 drop is 1 degree. Are the 100-200 numbers in ppm? Just want to make sure we are all seeing the same thing. If correct, this is moderately hard/soft water as suitable to a great many fish species.
 
As Steven noted there is no issue for plants here. And I believe we are in agreement that the water used for the tank(s) should not be coming out of the filter/softener but pre-filter/softener.

So that leaves the GH at 10 dH if your test was accurate. I am assuming the API test or similar where 1 drop is 1 degree. Are the 100-200 numbers in ppm? Just want to make sure we are all seeing the same thing. If correct, this is moderately hard/soft water as suitable to a great many fish species.
Correct. This is the one drop at a time, API GH/KH testing kit.
 
Now I’m wondering if I can swap my other tank over to just my tap water. I’m currently using half tap and half RO from the LFS.
If I want to try to switch it over, how should I go about this?
 
Now I’m wondering if I can swap my other tank over to just my tap water. I’m currently using half tap and half RO from the LFS.
If I want to try to switch it over, how should I go about this?

First question, what fish species are in the tank getting half RO?
 
First question, what fish species are in the tank getting half RO?
It’s fully planted with 1 betta, 2 otos, 2 nerite snails. Lots of pest snails, which I am allowing to stay, to help with my second tank feedings which will be pea puffers.
 
It’s fully planted with 1 betta, 2 otos, 2 nerite snails. Lots of pest snails, which I am allowing to stay, to help with my second tank feedings which will be pea puffers.

Bettas are obviously soft water fish, but I am certain than many betta keepers have water close to 10 dH. I'll let them speak for themselves.
 

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