CS100

I've been using CPR Aquatic products for 20+ years, and have always their products to be nothing short of the best design and quality. Also, it should be noted that the recent one star rating from the other reviewer should be disregarded as operator error. Make no mistake, this overflow box works precisely as it was designed. That design includes a nipple at the top of the elbow, as is plainly seen in the pictures accompanying the product page. The purpose of that nipple is to accommodate a dosing type pump, such as a TOM Aquarium Aqua Lifter Pump, in order to proactively remove bubbles of air that inevitably get trapped inside the elbow. This occurs with 100% of overflow boxes of this design, and CPR was smart enough to implement a solution for you, unlike most of other overflow boxes on the market.

Absolutely awesomeness. NOTE the Toms aqualifter is a MUST to run this system at its best. Once it’s rolling it’s all good. Quite expensive but in the saltwater hobby everything is.

Works beautifully, but absolutely want to use a pump.

works good on my 125 gal.

Works great!

cant keep the prime we have to keep sucking out the air through the tube. why???Update; Jan 24, 18I have to keep my original rating, this is the worst overflo system I ever had. As far as the prime we have been able to stabilize it with water balance and keep the filter bags and sponges clean. The problem with the box is apatesia!! I don't have a single apatesia in my tank, they have all grown in the under side where you can't get to unless u drain the tank, big job.In my opinion this overflo system is to much trouble and hard to clean and it will mess up ur water balance. Hope it helps