Which fish would best suit my FOWLR set-up?
I recently set up my first marine tank — a FOWLR system. It holds around 400l/88 gal after the addition of the rock, has a protein skimmer and lots of water movement. I am currently keeping a Flame angel and a Valentini puffer and I will be adding either a Kole or Purple tang in due course.
I am putting in new fish at the rate of one a month and would like to include a butterflyfish and a larger Angel in this mix. Any tips on the best choices here? THOMAS KIRBY, BY EMAIL
DAVE SAYS: A FOWLR set-up is ideal for the types of fish you are choosing, as it enables you to keep varieties that you wouldn’t otherwise be able to keep in a reef due to their habit of eating corals and other invertebrates.
For butterflies, the Red Sea-endemic Addis butterflyfish (Chaetodon
semilarvatus) is a superb, if expensive, choice for a FOWLR as it’s very hardy and doesn’t fall into the obligate corallivore (feed only on coral) category of many of its relatives. It’s a stunning fish but does get quite large, reaching 20cm in length. You’re probably safe keeping a single specimen in 400l, but a pair would need more room.
Klein’s butterflyfish, C. kleinii, an Indo-pacific species reaching 15cm in length, could be a more affordable choice – and you could certainly try to establish a pair in this size of tank. Klein’s are very hardy, too, and adapt well to captive diets.
Whichever species you decide on, avoid any which rely either entirely or partially on a diet of coral polyps. The larger angels from the genera
Pomacanthus and Holacanthus need hundreds of litres of water as adults, and even the medium-sized
Apolemichthys and Chaetodontoplus species will be quite cramped in 400l, which could create problems. Perhaps consider a Swallowtail angel,
Genicanthus spp. A male-female pair of Ornate angelfish (Genicanthus bellus) could be an option. They are attractive fish which grow to around 15cm in length and feed from the water column. They’re definitely not as commonly seen as they deserve to be, and are something a bit different to the norm.
Establishing a pair is easy as they are obviously sexually dimorphic; males have a yellow stripe running down the grey body, whereas females have black and blue stripes. If given a mature tank and plenty of open swimming space, while still having access to rocky outcrops to make them feel secure, these should do well.
Addis butterflys need excellent water quality.
A Swallowtail butterfy female.