I have a G4 pro. I have been reading about several quality control issues with the g5. Popping sounds, some kind of plastic cracking around the screws. Super noisy fan. And horrible mobius software. I have ecotech power heads, return pump and light all ran off a reef link. I hope maybe from the initial roll out maybe they got things straightened out. I have had good customer service with them. I even bought a used M1 from gateway and it rusted out. They sent me a m2 for free.