How do you delete a tank on happy aquarium?

what ya ment to do is sell all ya fish or move them to the other tank and at the top it will appear 'dELETE BUTTON' click that and it gives you options -

1. Delete your tank

2. Delete your tank AND your crops and fishes in it

3. Cancel

anyway havn't been on it for a year or somethin so it might of CHANGED NOW!