Flagtail Prochilodus – COLOR CHANGES through life-span

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FJB

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We hear about difficulty recognizing between the 3 species supposedly in the hobby: Semaprochilodus insignis, S. taeniurus, and S. laticeps. Difficult to recognize in aquarium fish, since the characters are mainly about counts of scales and counts of rays on fins, not aquarium-possible characters.

We also hear about Red Tail, Yellow Tail, High Fin, Short Body, and other terms applied to “Flagtail Prochilodus” that may refer to anything from actual species, to varieties of single species; they may also partly refer to inter-specific variation due to provenance (actual geographic variation), but also to ontogeny (age and development of individual fish), and possibly varying conditions in aquaria.

In the pictures below there is a single fish, shown at various times over a 3-year span. I purchased it at ~ 2.5-3 inches in September 2017. He (she?) is about 10 inches today and very friendly. The first set of pictures are all around the same date, the adult pictures shown were taken sometime on 2019, and the last May 2020.
The main changes I can see include: 1) Spotting on body becoming much less with age, and the spots become proportionally smaller in larger fish; 2) Color of the dorsal fin changes dramatically, appearing less banded (and less attractive) in older fish; 3) Red coloration on caudal fin (tail) and anal fin becoming more intensely red with age. Tail on the young fish was more yellow than red, but the ventral pair of fins were red from the beginning.

Have you had your Flagtail for long? Have you noticed color or shape changes? Would you show pictures of your Flagtail of any type and color? Cheers!

Semaprochilodus 31Dec2017 comp.jpg

Semaprochilodus_14Apr2019_IMG_6078.jpg

Semaprochilodus IMG_0557 Crop.jpg

Semaprochilodus + Pterophyllum 28May2020 latB IMG_0668.JPG
 
I got my flagtail in november of last year at around 2.5". It looked similar to yours as a baby as well. Now he's probably a hair over 9" and the difference I see in mine vs yours is his body is completely barren of the black spots he had as a child. I also notice my flagtail has a more oversized dorsal fin. I will say this, flagtails are the best cure all for aquarium eye sores I've ever had. Snails? Gone. Algae? Gone. He keeps an entire 9x5x2 aquarium clean by himself. I swear everyone should keep one if their tankmates will tolerate them.

Achara 2 - Copy.jpg

March27 Fei Feng - Copy-2.jpg
 
I got my flagtail in november of last year at around 2.5". It looked similar to yours as a baby as well. Now he's probably a hair over 9" and the difference I see in mine vs yours is his body is completely barren of the black spots he had as a child. I also notice my flagtail has a more oversized dorsal fin. I will say this, flagtails are the best cure all for aquarium eye sores I've ever had. Snails? Gone. Algae? Gone. He keeps an entire 9x5x2 aquarium clean by himself. I swear everyone should keep one if their tankmates will tolerate them.

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An inch a month of growth???

I thought these guys grew slow
 
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Thanks All for the responses. I agree completely with Blakewater Blakewater that these are among the best maintenance crew fish available. Never rest.
I also agree that your fish appears to have a taller dorsal fin than mine, and has fewer black spots left. An absolutely beautiful fish, looking very healthy.

I hope the overall coloration of the flagtails, including the fins, remain colorful into advanced age (whatever many years that may be... I don't know). Other fish, for instance the African Distichodus sexfasciatus and D. lussuoso, are beautifully colored as juveniles, but gray-out into annonymity (bland colors) as full grown fish. I used to have one of each, years ago. Nice fish but not very nice friends to other fish.
 
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An inch a month of growth???

I thought these guys grew slow
Thats what I thought too. I expected to leave him in the growout for a while but he grew fast enough to keep up with all the bass he was with. I assume it has to do with it being in such a large tank which provided it with a lot of surface area to clean. I believe my species is also the largest growing so it might have a slightly quicker growth spurt as a child. I will say, it seems to be slowing down now. All his growth seems to be in his girth at the moment. Getting to be a rotund little fish
 
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Your smaller new flagtail 6" has a really tall dorsal fin.
Yeah, IDK what to make of it. Do you? Is it a gender thing, or does the dorsal height vary naturally, or is it sometimes bitten off, I mean a portion of it, and never grows back fully, or what?
 
I just don't know. Blakewater Blakewater 's 2nd picture also has a very tall dorsal fin.
Beautifull fish, thanks!
 
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