Aquarium Arched Cave (M) This cave is perfect for nano fish and bettas! Please check the dimensions at the end of the description to make sure this is the right product for you. This underground natural looking cave is the perfect accessory for an original and eye catching tank! FIsh love to swim and hide inside it, this cave offers a darker place for them to feel safe and relaxed away from bright aquarium lights You have room in this cave to match your surface aquascape or to create a whole new contrasting underground world! This small cave will be very easy to clean with aquascaping tweezers! Pictures showcase the cave in a UNS 25 cm nano cube Dimensions: 200x60x53mm Opening: 90x28mm 8x2.4x2.1 inches Opening: 3.6x1.1 inches Custom sizes can be made (contact me directly)