they are wrong. sodium thiosulfate breaks down chloramine. however resid
ual ammonia
is left which needs to be removed by biofilters

"Sodium Thiosulphate - inorganic sodium thiosulphate is incredibly inexpe
nsive and
fast working. It is added to the chloramine containing water. The thiosul
phate
destroys the chloramine molecule and also effectively neutralise chlorine
,
unfortunately the resulting ammonia still needs to be dealt with if your
tank is
running at a very high pH. In a discus tank of pH of 6 this ammonia would
be
converted to the much less toxic ammonium and would over time be consumed
by the
filter bacteria etc.

S2O3 + NH2Cl + H2O ® SO4 + H+ + HCl + NH3

On Sat, 9 May 2009 14:08:34 EDT, Hal wrote:
"The following stock solution of Sodium Thiosulfate does not treat for
Chloramine, only Chlorine."