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

Re: lowering pH in soft water...



Gitte writes:

> My 10-gal tank is finally cycled (with ammonia, not fish, but with plants).
>  Yesterday I removed 50% of the water and replaced it with RO water in
>  preparation for the new inhabitants.  This cut the hardness in half (now
>  GH=4 and KH=2) and the initial drop in pH was 0.5.  However, this morning
>  the pH is back to where it was, i.e. 7.5.  I have read about buffering, and
>  I guess that's what has caused the pH to rise back to its former level.  I
>  would like to lower the pH to about 6, and am wondering about the best way
>  to do this.  Peat in the filter?  Peat in a bag in the tank?  Tetra's
>  Blackwater Extract?  Or???  (This tank has an AquaClear mini filter, 
there's
>  no measurable ammonia, nitrIte or nitrAte).
>  
The <best> method is dependent upon a number of factors, including the fish 
being kept, and the additional side-effects that are acceptable.  Nitric, 
phosphoric, and muriatic acid are all very effective, and best diluted to a 
manageable concentratrion.  Phosphoric may cause some algae blooming, because 
it adds phosphate to the water.  They all will reduce  KH (buffering 
capacity) as well.  CO2 injection will have a pH-reducing effect.  If you use 
CO2, see what drop it brings before messing with the other stuff.  Peat will 
reduce pH, GH, and KH.  This is a good thing if you are planning for South 
American or West African fish.  It will also color the water, and that should 
be an acceptable outcome.

Bob Dixon