[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Altering tapwater with peat

>From: "wayne swaby" <wayne at waswa_fsnet.co.uk>
>Subject: Altering tapwater chemistry with peat
>Hi all
>A letter which recently appeared in a UK fishkeeping magazine advocates the
>use of Irish Moss Peat from the garden centre .  His method
>is pretty simple, he puts filter floss in the bottom of a leaky bucket,
>fills it with peat and then runs tap water through it.  He claims that pH
>drops from 8.3 to 5, and KH from 13 to 3.  He then adds untreated tap water
>to get his desired parameters.

This is what I do with Canadian sphagnum, except that I let mine sit in the
bucket for a few days to get it down to 4.2 or so.  How far and fast it
drops depends on the buffering (KH largely) of the water.

>I can see how pH would be reduced by the (humic?) acid contained in the
>peat, but can someone explain what brings about the change in hardness?

The peat fibers contain a large number of negatively charged sites,
adsorbing the cations rather effectively.

>Can anyone say anything for or against this method?  I'm currently getting
>together all the stuff for my first serious attempt at a high-ish tech
>planted tank and will gratefully accept the 200 saving from not buying an
>RO unit if its any good.

I've heard that if your water is quite hard and carbonate rich, peat takes
a long time to have much effect and a lot of peat.  It can really be
fantastic if your water is 'responsive' though.

>By the way, my tapwater has a pH of 7.4, I havent got around to measuring
>the KH yet, but I figure its going to be higher than ideal.  I'm going to
>inject CO2 24hrs a day (cant/wont afford a controller) so I figure at least
>the hard water would guard against a pH crash.

Alkaline (buffered) water will resist pH crashes, hardness (GH) wouldn't
affect it. I've actually used peat water and then added sodium bicarbonate
to add KH.  I don't do it anymore, although it's effective.  one has an
acid and a buffer in the mix, then.

>The budget for this project is spiralling way out of control, but I'll think
>about stumping up for the RO unit if the consensus of the list is that I
>need one.

My planted tanks have been really quite satisfactory with peat filtered
water, a good substrate (now a bottom layer of peat/potting soil/flourite
mix and a top layer of flourite/gravel), regular fertilizer and DIY CO2.
No way could I ever afford anything more expensive than that, and it works
for me.


Doug Karpa Wilson

Department of Biology
Jordan Hall
Indiana University
Bloomington, IN 47405