PVC Overflow Fish Tank No-drill Overflow. Not for sumps! It can take up to 15-20 gallons per hour, so if you want to run a pump with your sump system - this overflow won’t work. This is designed for drip system auto change. Condition is "New". This is a great overflow design if you don’t want to drill you fish tanks, but want to have auto water changing system. This design is dry fit, but can be glued if you’d like. Easy to setup and remove if needed. Will combine shipping- additional overflows +$5 per item. Thank you!