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Switching to RO water because my local tap water is scary. Want opinions on how to best remineralize?

utahfish

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I add potassium in the form of k2SO4 calcium in form of calcium chloride, magnesium in form of mag sulfate and a comprehensive liquid fert called easy green. Question? Is this enough to raise my KH above 1 or do i need to add something like baking soda to increase KH. Any help would be useful?
 

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Use calcium and magnesium carbonates and bicarbonates to raise the KH.
 

seangee

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What fish do you keep? My softwater fish have 0KH and I have no reason to increase it. (i.e. they get straight RO)
 
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utahfish

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What fish do you keep? My softwater fish have 0KH and I have no reason to increase it. (i.e. they get straight RO)
For now ten neons. Theres just so much conflicting info in this hobby that i wanted to try and get a consensus on KH
 

Byron

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For now ten neons. Theres just so much conflicting info in this hobby that i wanted to try and get a consensus on KH
OK, I was wondering about the fish species too. From your initial post with all the additives mentioned I had assumed this was a heavily planted tank with plants primary and fish secondary, so I didn't jump in. If you are more interested in the fish being healthy, use RO on its own. Or you could mix a bit of tap water in with it (if plants are present) but still keep the GH and KH very low, with an acidic pH.

My tap water is basically zero GH and KH (the GH is given by the water authority as 7 ppm which is basically zero). I have had soft water fish species in this water for 30+ years now, with no issues. In a discussion on CorydorasWorld a couple weeks ago, Ian Fuller mentioned that he uses straight RO for his cories with no GH/KH additives and he (like me) lets the pH lower to wherever it decides to settle. Provided one has soft water fish, this is ideal.

A quick comment on the conflicting information. Some of this goes back to the days when most areas in North America had moderately hard to fairly hard water, and livebearers were very popular fish. Areas with softer water found livebearers difficult to keep healthy, and most in the hobby knew nothing about GH and KH, only pH. Slowly, buffering became more prevalent. There was also considerably less documented information on fish physiology than there is today. The hobby has come a long way scientifically, but many still repeat the old myths and this is confusing.
 
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utahfish

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OK, I was wondering about the fish species too. From your initial post with all the additives mentioned I had assumed this was a heavily planted tank with plants primary and fish secondary, so I didn't jump in. If you are more interested in the fish being healthy, use RO on its own. Or you could mix a bit of tap water in with it (if plants are present) but still keep the GH and KH very low, with an acidic pH.

My tap water is basically zero GH and KH (the GH is given by the water authority as 7 ppm which is basically zero). I have had soft water fish species in this water for 30+ years now, with no issues. In a discussion on CorydorasWorld a couple weeks ago, Ian Fuller mentioned that he uses straight RO for his cories with no GH/KH additives and he (like me) lets the pH lower to wherever it decides to settle. Provided one has soft water fish, this is ideal.

A quick comment on the conflicting information. Some of this goes back to the days when most areas in North America had moderately hard to fairly hard water, and livebearers were very popular fish. Areas with softer water found livebearers difficult to keep healthy, and most in the hobby knew nothing about GH and KH, only pH. Slowly, buffering became more prevalent. There was also considerably less documented information on fish physiology than there is today. The hobby has come a long way scientifically, but many still repeat the old myths and this is confusing.
It is a planted tank. Crypts swords and some grumpy styrogen repens. Ive tried to do as much research as possible on which ferts are less harmful to the fish and also the most economical. Ive used a fert calculator, (rotolabutterfly) and figured out my dosing to keep the parameters for the plants and fish in an acceptable range but despite all that none of the calculators mention KH unless calculating the addition of carbonates like baking soda. Maybe KH isnt that big of a deal???
 
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utahfish

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On a side note my concerns about the KH are for the well being of the fish, not the plants. The calculator also doesnt mention the effect the calcium magnessium potassium have on PH, though im pretty sure there is a formula to figure it out???
 
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Byron

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KH does impact fish, but significantly less than does GH or pH. The GH is the most important. Taking a step back, your neons will without question be better off (health-wise) in water with zero GH and KH and a pH below 7. As soon as you begin adding minerals for the plants, the fish will be impacted, as they will also for any increase in KH and possibly pH. Keeping this minimal is obviously better for fish. This is primarily why fish and high-tech planted tanks do not really go together very well. I remember an article in Practical Fishkeeping a couple of years back which referenced studies showing that diffused CO2 during the day (only) even had a negative impact, which frankly is no surprise but still not well accepted.

KH is primarily a buffer for the pH to prevent fluctuations. If one is adding for example calcareous minerals (calcium and magnesium) for the plants, these will raise the GH and also the pH, depending upon the amount, and then as the plants use them the GH and pH lowers. It is true that in natural waters there is a diurnal pH fluctuation, but it is only a few decimal places. If this becomes larger in the aquarium, and from my forays into researching planted tanks it seems it can, the fish will not be in the best shape. This is one reason I use Flourish Tabs for the larger swords which need calcium particularly; the nutrients are not released into the upper water column as they are when powder/liquid fertilizers are added to the water, so the fish do not have to deal with the strain/stress but the plants still get the benefit.
 
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utahfish

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KH does impact fish, but significantly less than does GH or pH. The GH is the most important. Taking a step back, your neons will without question be better off (health-wise) in water with zero GH and KH and a pH below 7. As soon as you begin adding minerals for the plants, the fish will be impacted, as they will also for any increase in KH and possibly pH. Keeping this minimal is obviously better for fish. This is primarily why fish and high-tech planted tanks do not really go together very well. I remember an article in Practical Fishkeeping a couple of years back which referenced studies showing that diffused CO2 during the day (only) even had a negative impact, which frankly is no surprise but still not well accepted.

KH is primarily a buffer for the pH to prevent fluctuations. If one is adding for example calcareous minerals (calcium and magnesium) for the plants, these will raise the GH and also the pH, depending upon the amount, and then as the plants use them the GH and pH lowers. It is true that in natural waters there is a diurnal pH fluctuation, but it is only a few decimal places. If this becomes larger in the aquarium, and from my forays into researching planted tanks it seems it can, the fish will not be in the best shape. This is one reason I use Flourish Tabs for the larger swords which need calcium particularly; the nutrients are not released into the upper water column as they are when powder/liquid fertilizers are added to the water, so the fish do not have to deal with the strain/stress but the plants still get the benefit.
Thanks Byron youre always very helpful and i appreciate it. I do use the flourish root tabs as well and they seem to do well. Makes sense about what you are saying about the GH. I try to keep it at about 4 DGH because the plants seem to struggle when its below 4. I think ill stop worrying about the KH and focus on keeping my GH and PH stable and on the lower end. Thanks again. Also on a side note i switched my lights down to about 7 hrs a day and the plants are doing fine with less hours of light and are all algae free so far. So thanks for that tip as well!!!
 

Byron

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Thanks Byron youre always very helpful and i appreciate it. I do use the flourish root tabs as well and they seem to do well. Makes sense about what you are saying about the GH. I try to keep it at about 4 DGH because the plants seem to struggle when its below 4. I think ill stop worrying about the KH and focus on keeping my GH and PH stable and on the lower end. Thanks again. Also on a side note i switched my lights down to about 7 hrs a day and the plants are doing fine with less hours of light and are all algae free so far. So thanks for that tip as well!!!
You are very welcome.

Several years ago when my plants, the swords especially, were showing signs of calcium deficiency (ironically this looks like an excess of iron because the plants use iron instead of calcium for the cell stgructure of leaves and it creates the brown blotches which enlarge until it kills the leaves) I took the advice to increase the GH to 4 or 5 dGH by using Equilibrium (my tap water is zero GH/KH). I did this in the two tanks with large swords. It solved the plant issue, but a marine biologist got me thinking of what this was doing to the fish; some of the fish were fine with the 5 or 6 dGH, but I also had some wild caught fish that biologically preferred zero GH/KH. I stopped the Equilibrium and used the Flourish Tabs, replaced every 2-3 months. That was some five or six years ago and I have had no issues since with calcium deficiency. I also use Flourish Comprehensive minimally, primarily if not solely for the benefit of the floating plants which cover the surface in all my tanks.

The pH will find its place in any system, if we leave the GH and KH alone. I let pH do what it wants because this will be more stable than my interfering.
 

seangee

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I agree. 2 of my tanks are 0KH and I have no issues with plants as long as I make sure I have root tabs. The swords (and probably some others) struggle without these.
I even have vallisneria in the tank in my signature pic. This is known as a hard water plant which cannot cope with soft water. It certainly doesn't take over the tank like it did when it was a hard water tank but is doing just fine.
 
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utahfish

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I agree. 2 of my tanks are 0KH and I have no issues with plants as long as I make sure I have root tabs. The swords (and probably some others) struggle without these.
I even have vallisneria in the tank in my signature pic. This is known as a hard water plant which cannot cope with soft water. It certainly doesn't take over the tank like it did when it was a hard water tank but is doing just fine.
Thanks for the input. Im going to let the KH be and let the PH do its thing and just try to keep everything else i can stable and consistent.
 

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