[Clinton Parsons]

I didn't realize my tap/well water was so acidic. New aqua soil, water filtered for sediment added last friday, aerated and have crazy great flow so it's pretty oxygenated. Newly calibrated pH meter says my pH is 6.16. The lowest last night was about 5.58. The temp is 82.6 since (cycling.)

I had planned on setting it .8-1.0 below whatever is naturally, but if I set it to 5.14... that's really acidic. I know AS is acidic but wow. Is this why I can never keep shrimp alive in the past? I figured it was the copper pipes or something.

New API Kh/Gh test kits say KH is between 0 and one (hard to tell, no more than one. Maybe zero?) and GH is 4.


For as long as I can remember, those kH and gH values have been the same, with many test kits over the years.

I have an RO/DI chamber but I haven't been using it. I am just using two sediment filters and a carbon filter to purify my well water.


FWIW, there are no fish/plants yet.

 

[MCSLABS]

You have extremely soft water, wont take much to move pH in either direction.

 

[hbosman]

The easiest thing to do would be increase KH to 2 or 3 with baking soda. Increase it gradually though.

 

[Clinton Parsons]

What confuses me is that so many people say not to bother with trying to change the kH, that I will be chasing a dragon.... Others have a pH around 7 with similar gH and zero kH...

I should aerate a glass of tap water and see how it's levels compare to the water in the tank that's been with the humic/tannic acids.

 

[jeffkrol]

What confuses me is that so many people say not to bother with trying to change the kH, that I will be chasing a dragon....

Normally yes and I assume you meant pH..but yours is fairly low though not really problematic since most fish prefer a slightly acidic water. Not all obviously.

Others have a pH around 7 with similar gH and zero kH...

Problem is it is not buffered well..
Adding coral sand to your filter will boost buffering capacity..
It is not adjusting pH that is the most relevant but keeping it stable..

However, calcium is the most important
environmental, divalent
salt in fish culture water. The presence
of free (ionic), calcium in culture
water helps reduce the loss of
other salts (e.g., sodium and potassium)
from fish body fluids (i.e.,
blood). Sodium and potassium
are the most important salts in fish
blood and are critical for normal
heart, nerve and muscle function.
Research has shown that environmental
calcium is also required to
re-absorb these lost salts. In low
calcium water, fish can lose (leak)
substantial quantities of sodium

http://www2.ca.uky.edu/wkrec/InteractionspHEtc.PDF

nice little paper dealing w/ aquaculture but the principals hold..



and if I remember it correctly trying to adj CO2 via pH in a poorly buffered ( low Kh) tank is not very accurate..
table 2 is interesting.. Corrects by "alkalinity"...

 

[hbosman]

It's my understanding that you would need some buffering capacity so you can use the ph/kh chart to determine CO2 amount. Since you need to use values from the chart to set the controller, you would want to to have a kh value of at least 2. Otherwise, having a kh of zero wouldn't be a problem for most plants and soft water fish.

 

[Edward]

The pH -> CO2 controllers based on KH work only with high KH waters.
ADA does not use such controllers for a reason. They set a fixed bubble rate instead.