Oh yeah it can be done, but the only ones I have seen that actually look healthy have 8-10 NOs rather than 3. I have a friend who ran a 40 long with 4 NOs and it was an awesome tank full of softies,LPS, and a derasa that grew to be about 8".As long as you have a shallow tank and enough NOs I think it can work, But I would rather pay to replace a couple of VHOs rather than 3 or more NOs.