neon-like fish that’s often forgotten is the Celebesrainbowfish Marosatherina ladigesi. It thrives in hard water and makes an outstanding community fish. Admittedly, you’re getting yellow with the electric blue rather than red, but it’s still a stunning little fish well worth keeping alongside other hard-water fish such as platies or swordtails.
MP. & C. Piednoir
For tanks with water on the hard side, the Celebes rainbowfish Marosatherina ladigesi offers an
electric vibrancy similar to that of the neon or cardinal tetra.
The ram cichlid Mikrogeophagus ramirezi requires exceptionally warm, soft, and acidic
conditions to thrive.
Bolivian rams Mikrogeophagus altispinosus are not only small and generally peaceful, they are
perfect for planted tank enthusiasts since they tend to leave plants alone.
water chemistry that suits them and fish that
will tolerate high temperatures, they can be
a great alternative. It appears that the relative
viability of neons and cardinals varies by
region, so speaking to other hobbyists in
your area is a good way to decide which of
these species would be the better choice.
But what other options are there? One
The ram cichlid Mikrogeophagus ramirezi
is one the most widely traded dwarf cichlids
available. Besides its normal color form,
domesticated morphs such as the golden
ram and German blue ram are also popular.
While I’m as fond of the ram cichlid as
anyone else, I’m also very aware of the
problems many aquarists have keeping
On paper at least, some of the difficulties
come down to environmental requirements.
Unlike the majority of tropical fish, ram
cichlids need very warm water to survive,
between 82° to 86°F being appropriate. Keep
ram cichlids too cold and they’ll weaken and
die, but try and keep standard community
fish this warm and you’ll find them gasping
for breath and eventually succumbing to heat
exhaustion. Another reason rams don’t mix
well with community fish is their need for
soft, acidic water conditions. You’re aiming
for 3° to 10°dH and a pH of 5. 5 to 6. 5, which
would be incompatible with hard-water fish
such as livebearers. Filter bacteria don’t like
acidic water either, and below pH 6, biological
filtration becomes unreliable, complicating
things even further.
Ram cichlids also suffer from the usual
dwarf cichlid sensitivity to nitrate. Nitrate
levels above 20 mg/l cause real problems
for rams, commonly triggering outbreaks
of the protozoan infection Hexamita, which
is implicated in symptoms such as wasting
and hole-in-the-head disease. So besides
very warm, very soft, and very acidic
water, ram cichlids also need water that is
As if this wasn’t bad enough, inbreeding,
intensive farming practices, and the widespread
use of antibiotics has meant that the quality of
many of the ram cichlids available in the trade
isn’t particularly high. All things considered,
it’s hard to recommend them. But oddly
enough, they have a very close relative of
very similar appearance that makes a superb
community tank resident. Indeed, it could be
described as the single best all-around cichlid
in the hobby! It’s colorful, hardy, peaceful,