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electric molecular
Wed Dec 21, 2005, 11:54 PM
Hey all,

After my LFS guy accidently sold me Kh up instead of pH plus, just wondering what people think about adding stuff to achieve a stable pH--is it better to simply add a pH buffer or is it better to raise the carbonate hardness? Is there any difference in terms of discus being comfortable in the water?

Claire.

DarrenJThomas
Wed Dec 21, 2005, 11:58 PM
If you are going to use a ph adjuster i would reccomend getting a phosphate free as this will not increase the nice stuff that algae like to live off.

Mulisha
Thu Dec 22, 2005, 02:28 AM
adding KH powder will raise your hardness if your growing fish up that's fine to have a 4 - 6 degree of KH but if you are breeding maybe a slightly lower PH and KH for them and the KH powder will stablize your ph much better the ph booster but will raise your ph as well..

for example you have ph of 7.0 and kh of 1.0 you add some KH powder you may have ph of 7.5+ and should have a stable kh at like 5.0 or do but this will stay like this and be very stable..

HTH :wink:

fishgeek
Thu Dec 22, 2005, 08:02 AM
is it better to simply add a pH buffer or is it better to raise the carbonate hardness?

carbonates are a pH buffer

pH is simply the number of free hydrogen ions in the water( pH ~ power of hydrogen)
kH is a measure of carbonate and bicarbonate ions in the water and they are capable of binding with free hydrogen ions , they do not neccesarily have to increase the pH although that is typical

there are other buffer systems, the bicarbobate system is what is used inside mamalian bodies
phosphate buffers have been mentioned and will not be in a kH up product(shouldn't by definition) becasue they do not add carbonates
the warnings about algal utilisation of phospates are worth baring in mind

i believe that something along the lines of hummins/tannins leached from peat has a pH stabilising effect on water

seachems acid buffer is supposed to turn carbonates to CO2 fro plant utilisation, i have heard though that the dropped pH that it cause's is not always stable, ie after time it can rise again

you water will inherently have a pH it comes at , additions of natural products/processes in your tank - ammonia alkaline, phophates in food buffer, denitrification in tank acidification
will tend to want to change your pH
regular water changes will tend to fight this trend if you are having to cange water to often for your liking then adding a carbonate buffer(baking soda) can help
if you wish your pH to be lower and stable then in my experience peat water treatment seems to work

mind , saying that i have very hard tap water , which i r/o filter and then peat treat, kH reads nil and pH 5-6 depending on peat contact times etc is always very stable

unfortunately not everyone's water is the same and so some experimentation on your own water , once you have gained some understanding of idea's is the only real choice

i would try your buffer solutions, boiling some peat and adding a few different amounts to your water,and just plain old water in teat buckets and see what you get
then leave them all aerating vigourously a few days and see what changes

then get some acid(weak like vinegar) add a couple of drops see how well the water copes
can also be done with stronger acid, car battery is an easy source, and again see what happens

that at least gives you an idea of what the water may react like in your tank
with time
and with the slow acidification that often occurs in tanks

have fun andrew