Any Advise Please

Yoyo loaches should really be kept in groups, but a 20 gallon tank (assuming that's what you mean, not 20 litres) is too small for them. The best thing to do would be to rehome it - perhaps exchange it for something more suitable. In a 20 gallon tank, there are no commonly available loaches that are suitable, but half a dozen of something like one of the dwarf corydoras (Corydoras pygmaeus the pygmy cory, or C. hastatus, or C. habrosus) would fit nicely provided the tank had sand or smooth gravel.

Just to check - what exactly is the dwarf plec? Some sold as dwarf do get too big for 20 gallons.








And if you mean 20 litres rather than 20 gallons, there are very few fish suitable for a tank that size.

Yoyos should really be in a group of at least 4, preferably at least six. But there is no way that many would fit in your tank as they grow to around 5 to 6 inches (unless they get stunted) and need a 70 gallon tank. It would be kinder for the last loach to rehome it with more of the same kind.

If the plec is an albino bristlenose, you might get away with it. They need tanks that are a minimum of 60cm wide x 30cm front to back.