Water hardness

Brendanpat

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Hi . I found out my water supply fluctuates between 100 -150 ppm . Because its comes from mixed sources. Is this suitable for my guppies ,mollies, corydoras ,Otocinclus and swordtail ? Should I put some coral in to harden it more ?
 

AdoraBelle Dearheart

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Guppies, mollies and swordtails like it hard, but the otos and cories need much softer water. You're going to need to rethink I'm afraid. They can't all live happily together in the same tank for their whole lifespans, since water hard enough for the livebearers is going to be too hard for the cories, and especially the otos
 
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Brendanpat

Brendanpat

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Guppies, mollies and swordtails like it hard, but the otos and cories need much softer water. You're going to need to rethink I'm afraid. They can't all live happily together in the same tank for their whole lifespans, since water hard enough for the livebearers is going to be too hard for the cories, and especially the otos
Thanks for reply . So it's hard enough for the guppies mollies swordtail the way it is ?
 

Naughts

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It is suitable for the cories and otos.
The guppies, swordtails and especially the mollies will struggle as they are hard water fish.
You would need to seperate the livebearers in a second tank and add minerals to their water.
 

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I concur, the GH at 100-150 ppm (5-8 dGH) is much too soft for any livebearers. Over the next weeks they will slowly weaken because their internal physiology requires calcium especially in the water and it is lacking. They will become more susceptible to disease and other issues because this weakening is significant and long-term. There is no "recovery."

The cories and otos are fine. While they can probably manage with some increase in GH/pH (the two are connected but it is the GH that is most crucial here) there is a limit how high one can go. A GH of 10 dGH (180 ppm) would be absolute minimum for guppies, but it should be higher for other livebearers, and for mollies significantly higher.

Increasing GH is fairly easy, either by using a calcareous sand substrate (which slowly dissolves calcium and magnesium) or using a preparation that adds mineral salts; note this is calcium and magnesium mineral salts, not common salt which is not needed. This method requires preparation of all water change water outside the tank.

The easiest and safest course of action would be to remove the livebearers and acquire fish that thrive in moderately soft water which is what you naturally have. It makes your life simpler too, in doing water changes.
 
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Brendanpat

Brendanpat

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I concur, the GH at 100-150 ppm (5-8 dGH) is much too soft for any livebearers. Over the next weeks they will slowly weaken because their internal physiology requires calcium especially in the water and it is lacking. They will become more susceptible to disease and other issues because this weakening is significant and long-term. There is no "recovery."

The cories and otos are fine. While they can probably manage with some increase in GH/pH (the two are connected but it is the GH that is most crucial here) there is a limit how high one can go. A GH of 10 dGH (180 ppm) would be absolute minimum for guppies, but it should be higher for other livebearers, and for mollies significantly higher.

Increasing GH is fairly easy, either by using a calcareous sand substrate (which slowly dissolves calcium and magnesium) or using a preparation that adds mineral salts; note this is calcium and magnesium mineral salts, not common salt which is not needed. This method requires preparation of all water change water outside the tank.

The easiest and safest course of action would be to remove the livebearers and acquire fish that thrive in moderately soft water which is what you naturally have. It makes your life simpler too, in doing water changes.
Thanks . That's sounds like the best road for me to go down .although I love my guppies and mollies . Could you tell me what other species would be suitable for my water ?
 

Byron

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Thanks . That's sounds like the best road for me to go down .although I love my guppies and mollies . Could you tell me what other species would be suitable for my water ?
Almost everything except livebearers and some rainbowfish (some are soft water, some moderately hard), and rift lake cichlids. So that means most of the fish from South America (tetras, hatchetfish, pencilfish, catfish like cories, plecos, etc, dwarf cichlids) and SE Asia (rasboras, danios, barbs, gourami, loaches). That is for the water. The tank size and your fish likes will help narrow it down. There are other criteria, like swimming activity levels, temperature differences, compatibility, how the tank is aquascaped (substrate, plants, wood, rock, etc).

Edited to clarify text.
 
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Brendanpat

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Almost everything except livebearers and some rainbowfish (some are soft water, some moderately hard), and rift lake cichlids need quite hard water. So that means most of the fish from South America (tetras, hatchetfish, pencilfish, catfish like cories, plecos, etc, dwarf cichlids) and SE Asia (rasboras, danios, barbs, gourami, loaches). That is for the water. The tank size and your fish likes will help narrow it down. There are other criteria, like swimming activity levels, temperature differences, compatibility, how the tank is aquascaped (substrate, plants, wood, rock, etc).
That's what I have at the minute .very basic but I'm only started my new hobbie about 5 months . Plenty to learn
 

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Nice looking tank but I would suggest replacing some plastic plants with live plants. Live plants improve the quality of the water, add oxygen and take away CO2 and most importantly absorb ammonia. I had plastic for years but have switch to live now for two years and will not go back. There are plenty of easy to care for plants that you do not need soil for. I would add a few more plants than what you have to give the fish cover.
 

utahfish

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Hi . I found out my water supply fluctuates between 100 -150 ppm . Because its comes from mixed sources. Is this suitable for my guppies ,mollies, corydoras ,Otocinclus and swordtail ? Should I put some coral in to harden it more ?
Cory and ottos are soft water fish the other you mentioned are hard water fish that like it 200ppm or higher.
Cory and otto wont do well with that high GH
 
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Brendanpat

Brendanpat

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Nice looking tank but I would suggest replacing some plastic plants with live plants. Live plants improve the quality of the water, add oxygen and take away CO2 and most importantly absorb ammonia. I had plastic for years but have switch to live now for two years and will not go back. There are plenty of easy to care for plants that you do not need soil for. I would add a few more plants than what you have to give the fish cover.
Must look into real plants too. Thanks .Are there special plants for aquariums ?
 
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