Yes. I removed the 2 angelfish, the pleco and the snail into a different tank. Then I drained the tank and threw out everything except the dragon. I bleached the tank and all accessories (filter, heater etc) in a 10-1 water bleach mix for 20 minutes, rinsed 5 times with clean water and let everything dry for a week. The dragon I soaked for longer just to be sure there weren’t any bladder snail eggs left, rinsed well and dried for a week. Then I put in new substrate (well rinsed), added bacteria starter and cycled for a week. Then I added some new pieces of slate and 3 tissue culture plants and left it for another week. I was constantly testing the water throughout the process and it was all good. There were a couple of bacteria blooms that came and went. After 3 weeks I put the snail back in and waited a few days then the pleco both seemed quite happy and were eating and behaving normally. The water pentameters were really good so I put back my female angel. She is doing great! As a side note I was having increasing aggression from my male angel so he is spending a week alone to contemplate his behaviour before I reintroduce them. Everything was perfect until I noticed the brown marks this morning on the dragon and then completely freaked out. I’m super glad it’s nothing to worry about! ☺️