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 Kribensis cichlid is a hardy fish that can adapt to both acidic and alkaline conditions. A pH-value in the 6.8 to 7.5 is the safest bet, but many specimens are able to adapt to more acidic or alkaline waters as long as the change is slow and gradual. In the wild, Kribensis can be found in both soft and hard waters.