Oh yeah best i inform you now, always forget, channa are escape artists, ensure any small gap/hole. are fully covered, either with something like gaffa tape or bung it up well,use cloth<old ripped tshirt in mine, crammed in the tape over, If you do find ones escaped place it back in tank first, before thinking its dead, they have the ability to stay alive out of water, even when dried...Just another member just said his escaped and found them dried up this morning, shame, but reminds me to remind others..Duckweed is a cheap and good option which may help them feel more secure,get a full covering in the tank,also the more planted the tank the better..