If you mean is it ok to have a 350 litre tank as a coldwater tank ? then yes you can
Seems like a wierd question , cant make it out,

Oh now, I sorta get it, u mean use cold water for water changes ?
I think this is fine, but it depends on how much for change, cause more could affect the temperature too much and make your fish ill.
I personally dont use coldwater, i first heat it with a aquarium heater, then add it to tank, after dechlorination
Is It Ok To Al Cold Water In A 350l Tank for water changes?
/www.fishforums.net/index.php?showtopic=149227