Cleanup Crew

Sooner or later is it likely that algae of one type or another becomes more difficult to control. It’s natural and normal to have some degree of algae living and growing in your aquarium. The control of algae from becoming so extensive that it causes oxygen depletion is the task of the aquarist. Most likely you have been controlling the amount of algae by scraping or scrubbing the algae off the walls of the aquarium as well as off the decorations and rocks.

Perhaps my favourite scavenger of the various algae is the ‘Florida fighting conch’ (conch snail), Strombus alatus. Strombus alatus is a ‘true conch’, a gastropod mollusk in the family –  Strombidae. It is actually a very peaceful, reef safe snail that is easy to keep; and ‘fighting’ is a misnomer but is derived from the fact that sometimes male conchs can be territorial.

I tend to refer to these ‘Florida fighting conch’ snails just as the ‘Florida conch’, even though more officially they are the ‘conch snail’; but I do this to distinguish them from the conch snails of the Indo-Pacific.

This conch snail sometimes grows to as large as 11.2 centimetres (4.4 in), but typically grows to about 5 centimetres (2 in). When you envision islanders blowing through a shell as though blowing a horn, this that kind of snail – albeit smaller in overall size. Conch snails love a sandy substrate, but will dig and ‘root around’ in gravel and crushed shell substrate too. They do this digging and rooting around to hunt for food, and by so doing they keep the substrate well maintained. They are easy to keep because among other things, they are quite tolerant of various water conditions – but of course, they do best in good and stable water conditions. For a 30 gallon aquarium, 1 or 2 of these snails works very well; and for a 55 gallon aquarium, 3 of these work great.

Some warnings though for keeping these snails: 1) hermit crabs (decapod crustaceans) frequently kill conch snails to obtain their shells, and 2) even trace amounts of copper, often from medications, can be lethal.

So, why is the ‘Florida Conch’ my favourite snail for scavenging various algae – it’s because they are voracious omnivores. They will eat hair algae, cyanobacteria (blue-green algae), diatoms, filamentous algae, leftover food, and even detritus! Of course, they love to eat green algae too, and is often their preferred food. What is important is that they will need a lot of the various algae to feed upon – did I mention that they are voracious?! Once they have eaten so much algae that what remains is insufficient for them to forage, just supplement them with dried seaweed. I have also found that they enjoy the various tablet food formulated for ‘Plecos’ (Hypostomus plecostomus) and ‘Cory Cats’ (Corydoras sp.).

Other possibilities for the cleanup crew are the: Dwarf Ceriths (small snails that feed at night mostly on green algae, but can get into very small places), Nassarius vibex (small scavenger snails that eat leftover food and a small amount of fish waste), Florida Ceriths (small, nocturnal snails like the Dwarf Ceriths, but feed upon hair algae, cyanobacteria, diatoms, and filamentous algae), and Nerites (small-medium size snails that are good eaters and feed upon hair algae, cyanobacteria, diatoms, and filamentous algae). For a 30 gallon aquarium, you’ll need about a dozen of each type of these snails, and it’s better to have 2 dozen of the dwarfs; for a 55 gallon aquarium – about double what you need for a 30 gallon aquarium.

There are snails that should not be part of the cleanup crew for a variety of reasons (not reef-safe, get to big for the home aquarium, carry parasites, etc.). These include the: Flamingo Tongue Snail (Cyphoma gibbosum), Bumble Bee Snail (Engina sp.), Murex Snails (Murex sp.), Eastern Mudsnail (Tritia obsoleta, formerly – Ilynassa obsoleta), Margarita Snails (Margarites pupillus), Crown Conchs (Melongena corona), Queen Conchs (Lobatus gigas, formerly – Strombus gigas), Keyhole Limpets (Fissurellidae; the entire family; these are not the ‘true limpets’), Olive Snails (Olividae; the entire family), and Babylonian Snails (Muricoidea; the entire family; these look like Nassarius snails).