USING lower WATT bulbs in HIGHER watt systems?

k so this is something i have been wondering for a while, i have limited space and my 400w is kinda hot, is it possable to use a lower watt bulb in the same system? like say a 150w or a 250w maybe?

id recon it would burn out ur bulb twice as quick
u probly have to change the ballast

mmm damn then

Hell no, your bulb will pop and burst into flames bro. Only use bigger bulbs on smaller systems than they are rated for, otherwise you are asking for a house fire.