The US sensors are present in the antennae of Mosquitoes and genetalia of Cockroaches. US emitted by the Repeller will scare away the pests and confuse them. Ultrasonic sound will create stress on the nervous system of insects and jam their own US frequency.
South America also houses several larger river cichlids. These species will often get along well in aquariums. For example, various species of freshwater angelfish and the discus fish make great tank mates.Both species prefer soft, acidic water and, importantly, grow to about the same size.frican cichlids prefer hard, alkaline water. Most are very aggressive, but in a large tank, dissimilar-patterned species can get along. You do want to avoid keeping closely related species together, since they may produce undesirable hybrids. For example, no two Auloncara species should share an aquarium.
The most ubiquitous aquarium hybrid is perhaps the blood parrot cichlid which is a cross of several species, especially from genus Amphilophus. With a beak-shaped mouth, an abnormal spine, and an occasionally missing. caudal fin (known as the love heart parrot cichlid), the fish is controversial among aquarists.