Armando, you can plumb your waste water to a sink in your basement. I pumo 5 gallons a day for my daily water change to a nearby sink that I installed in the garage. The sink is plumbed into the house drain but the waste water drain from the sump is pumped up to and into the sink. You do not want to plumb your waste water drain pipe into your main house drain without an air gap...the sink provides this in an easy manner. The reason you do not want to plumb directly into the house drain is that: 1. it is illegal and would nullify any home owners insurance. 2. if the back pressure is too great, for some reason like a flood or maintenance workers doing repairs, water could back up from the drain into your tank....not good.