Good stones and rocks to use that won’t raise ph?

DD1880

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I was going to delve into aquascaping for the first time and was wondering what we’re good stones or rocks to use that won’t raise my ph to much. I have hard chicago tap water that’s a ph around 7.8-8. I had what I think in my head to be some good ideas of valleys and maybe a land bridge over it. What rocks would be good to create that look of a canyon valley with a possible land bridge. I would like to keep cardinal tetras like I have now with some other South American fish but don’t want the ph to go to much higher. Thank you for any help!
 

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dw1305

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Hi all,
was wondering what we’re good stones or rocks to use that won’t raise my ph to much. I have hard chicago tap water that’s a ph around 7.8-8. I had what I think in my head to be some good ideas of valleys and maybe a land bridge over it. What rocks would be good to create that look of a canyon valley with a possible land bridge. I would like to keep cardinal tetras like I have now with some other South American fish but don’t want the ph to go to much higher.
It really depends on just how hard the water is. The pH on its own isn't a very useful measurement, what you really need, as well, is a measure of the carbonate hardness (dKH).

Our tap water is from a deep limestone aquifer, and about 18dKH. This water can't get any harder, or the pH rise, <"if I add a limestone rock">, because the water is already fully saturated with calcium (Ca++) and (bi)carbonate ions (2HCO3-).

If you <"aren't going to add CO2">? Just choose a rock you like in terms of colour and texture. It doesn't matter if it is a limestone.

If you do use CO2 there will be some erosion of the rock while the CO2 levels are elevated, and this <"will precipitate back out as "lime scale" when the CO2 is turned off">.

cheers Darrel
 

DD1880

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Hi all, It really depends on just how hard the water is. The pH on its own isn't a very useful measurement, what you really need, as well, is a measure of the carbonate hardness (dKH).

Our tap water is from a deep limestone aquifer, and about 18dKH. This water can't get any harder, or the pH rise, <"if I add a limestone rock">, because the water is already fully saturated with calcium (Ca++) and (bi)carbonate ions (2HCO3-).

If you <"aren't going to add CO2">? Just choose a rock you like in terms of colour and texture. It doesn't matter if it is a limestone.

If you do use CO2 there will be some erosion of the rock while the CO2 levels are elevated, and this <"will precipitate back out as "lime scale" when the CO2 is turned off">.

cheers Darrel
Thank you for the info! I’m pretty sure the water is hard and not soft. I don’t have a dKH tester. Only the api liquid test kit for ph, ammonia, nitrites, nitrates. I will not be using co2, yet. I was going for a dirt tank with a cap. Maybe black blasting sand? Was hoping to do a non co2 carpet of Monte Carlo! Maybe some Ludwigia Repens and Similar plants that would do ok without co2. I’ve been reading up on the walsted method. Not sure what would be best cap for the dirt to get adequate water flow? Would putting rocks and drift wood on top of the dirt and cap be a bad idea? I was hoping to do my first scape! Thank you for any help!
 
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DD1880

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Would like to do Ludwigia super red but not sure if it’ll do well without co2 or if they are the same as the Repens as far as needs to grow well? New to this planted tank thing but want to learn and will never not do a planted tank again! Also would like to do Rotala and bacopa if possible. Maybe crypt wendtii. Dwarf baby tears would be awesome but not sure it’ll do ok without co2 or if it’s possible in a non co2 tank that water column ferts only? I have a Chihiros rgb 60. Would that be enough light for these plants in a 29 gallon? Thanks for any help!
 

DD1880

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87F732FE-EDEE-49D9-A265-E53CE875E842.png
Hi all, It really depends on just how hard the water is. The pH on its own isn't a very useful measurement, what you really need, as well, is a measure of the carbonate hardness (dKH).

Our tap water is from a deep limestone aquifer, and about 18dKH. This water can't get any harder, or the pH rise, <"if I add a limestone rock">, because the water is already fully saturated with calcium (Ca++) and (bi)carbonate ions (2HCO3-).

If you <"aren't going to add CO2">? Just choose a rock you like in terms of colour and texture. It doesn't matter if it is a limestone.

If you do use CO2 there will be some erosion of the rock while the CO2 levels are elevated, and this <"will precipitate back out as "lime scale" when the CO2 is turned off">.

cheers Darrel
I found this about Chicago water hardness. Not sure what it means haha
 

dw1305

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Hi all,
I found this about Chicago water hardness. Not sure what it means
Perfect, you can convert the 137 mg/L CaCO3 value to dKH using: 1dKH = 17.86 mg/L CaCO3 and 137/17.86 = 7.67 dKH.

The derivation of dKH etc is in Larry Frank's very useful <"Water Hardness"> article at the Krib.

In terms of the rocks you can use it limits what you can use without raising dKH/dGH, because your water isn't anywhere near fully saturated with the ions that we measure (as dGH/dKH).

What about <"water rounded cobbles">? You wouldn't need to know what type of rock they were, only really hard rock forms rounded cobbles, and really hard rocks are (in practice) inert.

I don't know what you can get locally, but I would imagine you are well positioned because glaciers, during the last ice age, will have dumped a <"huge amount of glacial drift"> in Lake Michigan etc.

Have a look at @doylecolmdoyle's <"river tank">

27442955868_c9d66d48b3_b.jpg


cheers Darrel
 
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DD1880

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Hi all, Perfect, you can convert the 137 mg/L CaCO3 value to dKH using: 1dKH = 17.86 mg/L CaCO3 and 137/17.86 = 7.67 dKH.

The derivation of dKH etc is in Larry Frank's very useful <"Water Hardness"> article at the Krib.

In terms of the rocks you can use it limits what you can use without raising dKH/dGH, because your water isn't anywhere near fully saturated with the ions that we measure (as dGH/dKH).

What about <"water rounded cobbles">? You wouldn't need to know what type of rock they were, only really hard rock forms rounded cobbles, and really hard rocks are (in practice) inert.

I don't know what you can get locally, but I would imagine you are well positioned because glaciers, during the last ice age, will have dumped a <"huge amount of glacial drift"> in Lake Michigan etc.

Have a look at @doylecolmdoyle's <"river tank">

27442955868_c9d66d48b3_b.jpg


cheers Darrel
Thanks Darrel for the response and help! Haha here I always thought I had hard water! We do have lot of river stones like that around the lake. Not sure I wanted that look. More like a canyon wall for my valley. Would dragon stone raise the hardness to much? Is there any other stones besides river stones that won’t raise dKH to much? Also when laying the stones to make the valley should they go straight on the bottom of tank first and then lay dirt and then cap down? Thank you for any help!
 

DD1880

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Hi all, Perfect, you can convert the 137 mg/L CaCO3 value to dKH using: 1dKH = 17.86 mg/L CaCO3 and 137/17.86 = 7.67 dKH.

The derivation of dKH etc is in Larry Frank's very useful <"Water Hardness"> article at the Krib.

In terms of the rocks you can use it limits what you can use without raising dKH/dGH, because your water isn't anywhere near fully saturated with the ions that we measure (as dGH/dKH).

What about <"water rounded cobbles">? You wouldn't need to know what type of rock they were, only really hard rock forms rounded cobbles, and really hard rocks are (in practice) inert.

I don't know what you can get locally, but I would imagine you are well positioned because glaciers, during the last ice age, will have dumped a <"huge amount of glacial drift"> in Lake Michigan etc.

Have a look at @doylecolmdoyle's <"river tank">

27442955868_c9d66d48b3_b.jpg


cheers Darrel
These are some of the rocks the kids found in the back yard for their tadpole tank. Not sure what they are!
 

dw1305

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Hi all,
These rocks!
That one looks like it might be a Carboniferous (Mississippian or Pennsylvanian) age limestone, it has a bit of a "fossil coral" look (below is a <"Jurassic age one from the UK">).

tisburyStarstone.jpg
Would dragon stone raise the hardness to much? Is there any other stones besides river stones that won’t raise dKH to much?
A lot of rocks are inert, I don't think Dragon stone raises pH, but it isn't a rock I've used.

cheers Darrel
 

DD1880

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Hi all, That one looks like it might be a Carboniferous (Mississippian or Pennsylvanian) age limestone, it has a bit of a "fossil coral" look (below is a <"Jurassic age one from the UK">).

tisburyStarstone.jpg
A lot of rocks are inert, I don't think Dragon stone raises pH, but it isn't a rock I've used.

cheers Darrel
Thanks again! What rocks have you used? Have you used petrified wood? I was thinking about that for the canyon wall maybe.
 

DD1880

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Hi all, That should have been

"I don't like rock that doesn't look rounded and water worn".

cheers Darrel
Haha yeah I was a lil confused when I read it since you said you only use river cobbles! I like that natural look also.
 

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