I've got a good system here that I am looking to sell or trade for a nano or small sized aquarium.
The subwoofer is a Kicker CVX inside of a ported box. It can handle 750 watts RMS, hits hard!
The amp is a Hifonics Brutus Elite Mono Class D (Model BEX1750.1D) that is capable of 1700 watts RMS.
http://hifonics.com/bex-1750-1d/
I will include all wiring as well as a 150amp breaker.
$200