Homebrew PCBs

if you want to keep it "portable" you may try such a cooling container (the insulatet box for keeping 
things cold without active cooling system).
this has a lid on it.
but it is best for etchants which can stay there exposed to air and can be reused (regenerated) like the 
cucl with air regeneration.
(you have read all the cucl posts here?)

but if you want to try, for example one of the hydrogen peroxyde using processes i think it is better to 
have several smaller containers because the h2o2 is volatile. if you only use a small amount of etchant 
you only have to replenish a small amount of h2o2 to activate.

well, you have bought Ammonium Persulphate, i never tried this.
i don't know if it can be reused, is good to spray etc.

i would NOT recommend fe3cl. simply because a tiny drop stains everything.
i also don't like the etching speed (without suitable heating and agitation).
i still have some bags of fe3cl here which i never used. (here i'm talking about the cheap yellow stuff, 
not the "sublimate"? was it called so?)

are you sure you want to stay with Ammonium Persulphate?
you want to heat? agitation (bubbles?)?
having a bubbler on the bottom has resulted in stronger etching on the bottom (with cucl).


regards
stefan