As others have mentioned...my new Tetra box filter just wouldn't stay together. My husband put a bungee cord on it. My pump arrived Sat. Very heavy. Added small rocks to box filter to keep it on the bottom. The extreme hot weather has me running a sponge filter box filter and an aquarium waterfall filter. I have had to do water changes every few days. I use the fish water on my garden plants. As of this a.m. the box filter seems to have kicked in and water is a bit cleaner. Will decide if I keep the 100 gallon tub near the garage( outlets there). Or move it to more shade. Or may put a cover of some sort over it. I can't believe how much I've spent or how envolved I've gotten with this. Will be getting more water plants this week.