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.
If you have an algae eater, you may have been told to get a sucker fish, or algae eater. These fish have specially designed mouths that allow them to latch on to surfaces and suck off the algae. Some people call catfish sucker fish as well. Catfish usually clean waste off the bottom of the fish tank. These types of fish are a great addition to your tank, as they help to keep it clean. There are many different fish on the market that are commonly labeled algae eaters. Some are better at eating algae than others.