delusion of negation (nihilistic delusion) a depressive delusion that the self, part of the self, part of the body, other persons, or the whole world has ceased to exist. paranoid d's an older term for delusion of grandeur and delusion of persecution; its use is discouraged. delusion of persecution a delusion that one is being attacked, harassed, cheated, persecuted, or conspired against. It is one of the subtypes of delusional disorder.
Oto Catfish. These fish are perhaps the best kind of fish that you can get for the purposes of cleaning away algae from the plant matter in your fish tank. Their favorite type of algae to eat is brown algae, something that most other fish will stay away from.
Amano shrimp are by far the best algae eating shrimp available. Unfortunately, most pet stores do not have these types of shrimp available often. If your pet store has a few, grab 3 of them, because they do thrive in numbers of 3 or bigger. They will eat most algae, dead pant matter, and any left over food in the aquarium.