BH,
OK, it's a done deal now. I siphoned out several gallons of water into the plastic tub, put all the plants and ornaments in it, put in an air disc, put in the biowheels so they wouldn't dry out, then put in all the fish. Then siphoned all the water out of the tank, scooped the gravel into another tub, took out both plates and threw them in the garbage!, rinsed and siphoned both the tank and the tub of gravel and got out ALL the gunk that was under there! Then rebuilt the tank without the plates. Vacuumed the gravel one last time before filling up the tank. I went ahead and cleaned the impellers on the filters and replaced the sponges, which I have used for a long time (alternately rinsing them). Put the fish in last with as much water that I had taken out of the original tank as I could use. Also I put in BioCoat. I ordered the biospira this morning so it will be here Tuesday or Wednesday. So far, so good. The gravel is so clean it will blind you
So, I will check the water until the biospira comes, but I don't think it could get toxic in two days. I have in that tank: 5 clown loaches, 17 neon tetras, 4 angel fish, 5 penguin tetras, 2 red eye tetras, 2 red tailed sharks.

B)
By the way, this would have taken hours longer if I didn't have the python! I love that thing!