If I switch Tango's 16 over to Eco Complete and I keep all the decor, plants, filter media, filter housing (without the electric bits), filter intake, and heater in old tank water while I do this, can I avoid a huge recycle of the tank? I expect a mini cycle and I'll be monitoring, I just want to avoid huge ammonia swings. I've read that the bacteria can live without oxygen for 6 hours and I'm sure I won't need that much time. I'll add small handfuls of old gravel around in the tank too.
I'm switching for two reasons. My corydoras were fine for these six months on river rocks but I see now that one of them has a shorter barbel. I feel bad for the guy and I want to fix this before they all start to lose them. Also, I have a diatom problem and I think part of the reason is too many nutrients. The river rocks are medium sized and a lot of the time the cories pellets fall through cracks and decay there. I vacuum every week but in the meantime I have diatoms all the time.