Hello A1foxes.
Before you get too carried away changing things you need to determine the load of your fish room.
Most household wiring is 14 gauge wire which carries power through a 15 amp breaker. The breaker is max rated at 15 amps with a normal draw amperage of 13 amps or less, this difference allows for things like motors which have a high draw while starting up but draw much less when running at full speed.
Every 120 watts draws 1 amp so add all your heater watts, power filter watts and light watts along with anything else you have that uses power and divide your total wattage by 120 and this will give you your amperage draw.
Try to keep this total amperage draw under 13 amps and you shouldn't have breakers popping.
2 things to keep in mind is that if your load is close to 15 amps, flourescent lights draw more power to start up then to run once lit up so if you have a lot of fixtures wired together or plugged into one timer it draws a lot of power to start them. Second if you have old breakers that have popped numerous times they can become weak and pop prematurely even if your load is less than 15 amps. Hope this helps.
GBP