Re: [RML] Melanotaenia trifasciata - size

Bruce Hansen (bruceh at
Sun, 15 Aug 1999 12:01:00 +1000

Hello Michael

At 22cm that is a very large and old Tri and would have been raised in a
large tank for 6-8 years to get that big. Only one in a million gets much
bigger than 6-7 inches but old fish mah be almost half as deep as they
mwasure from snout to caudal peduncle. I had some Pappan Creeks that grew to
6" TL and I gave them to John Doley who put them outside in Darwin and he
said they grew another 2''. Neil Armstrong had an old female Goyder that was
supposed to be about 8".
The biggest rainbows I have ever seen in the wild were some Inornatas in a
pool in Laurie Creek in Arnhem Land - the ones we managed to catch stretched
right across an 8'' plastic bag and they weren't the biggest ones in the
They never seem to get that large in the wild or in small tanks. You should
be able to keep a nice school of 6-8 specimens in that tank and they should
grow to at least 5-6 inches over 3-4 years. Remember they like good water
quality and movement - try to direct the return from your power had along
the front glass and they will tend to line up in the current. Also don't
just feed them a carnivorou diet - they need at least 1/4 to 1/3 of
vegetable matter in their diet. Try to have at least 2 males in your school
too - to promote displaying and dominance which brings out the colours and
desire to spawn. Watch the nape stripes light up after a water change. No
wonder Adrian Tappin gave them the name "Regal" rainbowfish. They are truly
the kings of the rainbowfish world.

The PNG species may be spectacularly different but each trifasciata has more
colours of the rainbow than most of their more noprthern cousins


Bruce Hansen, A.N.G.F.A., Advancing Australian Aquatics.

Bruce Hansen, ANGFA, caring for our aquatic ecosystems.

Please visit us at

----- Original Message -----
From: Michael Haas <michael.m.haas at>
To: <rainbowfish at>
Sent: Sunday, 15 August 1999 7:35
Subject: [RML] Melanotaenia trifasciata - size

> Hi again!
> While evaluating the different sources I've noticed, that most of them
> say that the size of an adult M. trifasciata is 13 or 12 to 15cm.
> But at I found that "M.
> trifasciata can grow to approximately 22cm long and their bodies can
> attain a depth close to 8cm deep"
> Oh ha - that would be a lot to big for the space I could offer.
> I think, like other fish the size of the M. trifasciata depends on the
> size of the tank an the kind of foot that they get. Which size is to
> expect in a well plantet 140x60x60cm tank and a "diet" with frozen red
> an black mosquito-larvaes.
> Do you think that it is possible to observe the social-behaviour of M.
> trifasciata in a tank like this (our is it just big enough to keep
> them alive)?
> The more I think about that the less I believe it.
> Kind regards
> Michael