same thing happen to me my tank pulls alot of electricity since my house has alot of electronics running all the time the addition of my tank the breaker would trip once in a while. my dad thoughts it was an old breaker so we replace that one but still was happening.
we decided to do a dedicaded ( hope i spelled that right) circuit for my fish tank now no more problems and got plenty of energy to spare.
if you need a circuit to be ran i can ask my dad how much he will charge. pm me if you want me to find out