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Fry Size

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Recently, there has been a lot of comparisons of everyone's spawns. Some have fry well ahead of the curve while others seem to be lagging a little on what the 'accepted norm' currently is.

First and foremost: Fry will develop at their own speed dependant on a number of different variables. Do not panic if your fry are not growing as fast as another breeders. As long as your young are developing correctly and seem healthy, then keep doing what you're doing. In the end, if you take good care of them, they will all grow up to be beautiful adult fish.

I would offer these two links as the current 'norm' that everyone is measuring themselves by:

Wayne Schmidt's Betta Growth with Pics (Imperial) http://www.waynesthisandthat.com/bettagrowth.htm

Jim Sonnier's Raising Fry Growth Chart (Imperial) http://www.bettas-jimsonnier.com/raisingyoung.htm

Jim suggests a slightly slower rate of growth than Wayne...

To make things slightly simpler for metric only individuals...like me...below the measurements have already been converted for you:

(Wayne's chart only goes to week 11...hence no week 12/14/16 comparison)

4 weeks : ¼" – 3/8", or 6.35mm – 9.52mm, or .6cm – .9cm (Wayne – 1.14cm)

6 weeks : ½" – 5/8", or 12.7mm – 15.8mm or, 1.2cm – 1.5cm (Wayne – 2.1-2.5cm)

8 weeks : 1", or 25.4mm, or 2.5cm (Wayne – 3.3cm)

10 weeks : 1 + ¼", or 31.75mm, or 3.2cm (Wayne – 4.31cm)

12 weeks : 1 + ¾", or 44.45mm, or 4.5cm

14 weeks : 2", or 50.8mm, or 5cm

16 weeks : 2 + ¼", 57.15mm, or 5.7cm

I would suggest we make our own chart, but this will require input from many individuals over a long period of time and multiple spawns...or some combing through posted spawn logs (might give me something to do at work :)), but will be easier to keep up-to-date now that everyone knows we are trying to create our own version.

I'm happy to be the point man on this (seeing how I opened my trap, I might as well put in the yards as well), but would very much appreciate everyone's input.

Number One Rule - no adding millimetres to reports, but estimations to the half centimetre would be okay (rounding down).

So your four week old fry may be 5mm, 7mm, or 1.2cm or you could report it as half a centimetre or 1 cm (with 7mm being rounded down).

I know a lot of people currently have fry in the tank, so we may have missed some of the earlier measurements, but that's fine. We need to start somewhere. All you need to do is measure/estimate the size of your largest fry, and give me an average of what you think most of your fry are at, and lodge those measurements here (I've removed the request for the runts - we all have them and they either get eaten or culled most of the time). I will also need to know whether your fry are long fin or plakat, and give them a name (I'm not fussed if you call them black ninjas or BJT20140201 - just something unique please).

I'll create a spreadsheet to keep the data and work out the averages, and update that information in this thread. Feel free to send me odd-numbered weeks as well so we can have a full overview.

As Jim's chart is the lower of the two commonly accepted measurement charts, I will begin with that as my baseline (I have added a middle measurement for Jim's odd-weeks for completeness):

Measurements are total body length plus fins - so from snout to caudal edge.

Measurement guides are non-exclusive and so contain sizing from full finned specimens, full x plakats (mid fins), and plakat x plakat pairings. This will lead to an average across all types, but there is now separate charts for full fin and plakat as well.

AAQ Growth Chart (last updated 02/10/2014)

Week No Av +Gain Previous Mark (10/06/2014)

01 week : 0.45cm 0.43cm

02 weeks : 0.58cm + 0.13 0.53cm

03 weeks : 0.79cm + 0.21 0.76cm

04 weeks : 0.96cm + 0.17 0.97cm

05 weeks : 1.28cm + 0.32 1.21cm

06 weeks : 1.24cm - 0.04 1.22cm

07 weeks : 1.55cm + 0.31 1.55cm

08 weeks : 1.70cm + 0.15 1.70cm

09 weeks : 2.05cm + 0.35 2.05cm

10 weeks : 2.21cm + 0.16 2.21cm

11 weeks : 2.47cm + 0.26 2.46cm

12 weeks : 2.54cm + 0.07 2.56cm

13 weeks : 2.80cm + 0.26 2.84cm

14 weeks : 2.87cm + 0.07 2.92cm

15 weeks : 2.90cm + 0.03 2.93cm

16 weeks : 3.10cm + 0.20 3.16cm

The first half of the fry life, in regards to the growth chart, is now starting to stabilise, and even put on a millimetre or more. The second half of the fry growth chart continues to reduce. In general, it seems to take longer to grow the fish to maturity the further south from the Tropic of Capricorn the breeder seems to be.

I've managed to split the growth rates between plakats and fancy Betta from the spawn data I've been given. I'll keep the overall as is above and add in the two separate charts below: We seem to have more spawns targeted at the short fin at the moment. If you are breeding long fin, please consider adding your measurements to this thread.

AAQ Plakat Growth Chart (last updated 02/10/2014)

Week No Av +Gain Previous Mark (28/06/2014)

01 week : 0.45cm 0.47cm

02 weeks : 0.59cm + 0.14 0.53cm

03 weeks : 0.78cm + 0.19 0.71cm

04 weeks : 0.89cm + 0.11 0.86cm

05 weeks : 1.18cm + 0.29 1.03cm

06 weeks : 1.12cm - 0.06 1.06cm

07 weeks : 1.20cm + 0.08 1.20cm

08 weeks : 1.34cm + 0.14 1.34cm

09 weeks : 1.65cm + 0.31 1.65cm

10 weeks : 1.78cm + 0.13 1.78cm

11 weeks : 1.92cm + 0.14 1.92cm

12 weeks : 2.12cm + 0.10 2.12cm

13 weeks : 2.24cm + 0.12 2.24cm

14 weeks : 2.43cm + 0.19 2.40cm

15 weeks : 2.62cm + 0.19 2.38cm

16 weeks : 3.00cm + 0.38 2.58cm

AAQ Long Fin Growth Chart (last updated 02/10/2014)

Week No Av +Gain Previous Mark (No long fin spawns added/updated since mark)

01 week : 0.40cm 0.40cm

02 weeks : 0.54cm + 0.14 0.52cm

03 weeks : 0.83cm + 0.29 0.83cm

04 weeks : 1.35cm + 0.52 1.35cm

05 weeks : 1.48cm + 0.13 1.48cm

06 weeks : 2.00cm + 0.52 2.00cm

07 weeks : 2.60cm + 0.60 2.60cm

08 weeks : 3.15cm + 0.55 3.15cm

09 weeks : 3.25cm + 0.10 3.25cm

10 weeks : 3.50cm + 0.25 3.50cm

11 weeks : 3.57cm + 0.07 3.57cm

12 weeks : 3.40cm - 0.17 4.00cm

13 weeks : 3.73cm + 0.33 4.00cm

14 weeks : 5.50cm + 1.77 5.50cm

15 weeks : 4.05cm - 1.45 5.50cm

16 weeks : 5.50cm + 1.45 5.50cm

As you can see, if I get a weeks measurement here and there, and then large gaps of no data, then it has a significant impact on the numbers, but, any data is better than no data. Over time it will all average out, or I will do something like remove the highest and lowest and average it all out...

Always happy to get more data :D

Edited by Brenton

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This will be an interesting project. The discipline of taking weekly measurements might be a bit of a challenge. I'll see how I go with the next spawn I have.

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Weekly measurements would be nice, but even bi-weekly, monthly, whenever you remember - all would be useful for the overall data. I dont want to judge one person's growth rate with another, all graphed measurements and average totals will not have any identifying names attached to them. If anyone isnt comfortable posting measurements here, then send me a message with them and I'll add them on the quiet ;)

My F1 CTPK spawn hits the seven week mark this week (Thursday) - I'll be doing my first lot of measurements then. I wont be changing the baseline until I've got a few more.

So all that needs to be posted here is:

Mr Big: The size of your biggest fry

Runt: The size of your smallest fry

Average: A guess-timate of the average size of your over all spawn (or the actual average if you have a small spawn - wont matter the number will be used the same. Just be honest with yourself and with us :))

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Not just you - I've already added a reminder each week so I can remember - so when I do updates, hopefully that will remind everyone else...its when nobody adds anything that it could get tricky ;)

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The really young ones I would just herd with a net to the front glass so I can put a ruler next to them. The older ones you can do the same or actually lift the out for a second in the net. Or just have the net in very shallow water. Dunno I'll be playing it by ear.

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I've stuck a small paper ruler to the front of the glass near where I feed them and then wait for them to swim past :)

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Examples of how I measure my fry (Tip #1 use a camera and measure using the photos):

13.jpg Stick a paper ruler on the tank and wait for someone to swim by.

This guy is approximately 1.3cm

They don't have to be actually over the ruler to be measured. You can take a piece of string or cloth...something you can hold over the photo of the fry, and then move that gained measurement over the ruler you also have in the shot.


From holding a straight line over this guy, and then moving it to the ruler, I know this guy is around 1.2cm.

And they don't have to be swimming horizontally for this to work...just somewhere near the ruler:


Using a piece of cloth, I took the straight line measurement from nose to tail, and then transferred that across the ruler to know this guy is around 0.9cm (my runt :))

Lastly, know the measurement of different things inside your tank. Put centimetre markings on your ceramic pot before you put it in. Put a ruler on the back wall of your tank. Measure the different parts of your heater - that's how I knew the size of this guy...

15Thermostat.jpgHe's my biggest at 1.4cm

So my guys are far from huge. In fact, on both charts, they are a little behind where they should be. That's fine as I believe they are a week behind because they were the best part of a week late getting onto BBS from VE. I think they are also behind because they are a further week later than I wanted getting onto Grindals. But that's okay - they are forming well and just beginning to show some aggression, so I know they will get there in the end.

So...my numbers for almost week seven would be (I'll redo this on Thursday for accuracy-sake):

Mr Big: 1.4cm

Runt: 0.9cm

Average: 1.1cm

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Ok, I used a ruler as they thought it was feed time again LOL.

7wks old

Mr Big - 3.5cm

Ms Small - 2.5cm

Average - 3cm

Biggest is male & smallest is female.

Edited by JayM

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here BT.
dragon plakat spawn (no spawn log on them cause im lazy)
mid week four
each side of the triangle is .7cm (70mm)
runt .5cm (50mm)
hulk .9cm (90mm)
average(only a small spawn and most are the larger size) .7-.8cm (70-80mm)

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ok also for our copper/black lace bunch
end of week 5/start of week 6
mr big is almost 1.7cm
runt is only about .8-.9cm
average seems to be around 1.2cm
pretty much on track. although the runts pretty runty

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Thanks Jay!

Nope, Lorraine - as long as they are plakats or long fins, we'll take measurements. Bring on the VT x whatever....:D

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Would this help, Lorraine? http://www.ausaqua.net/index.php/topic/15486-adding-pictures-into-your-post-since-the-recent-upgrade/#entry173183

But I need to know the biggest, which looks to be about 1.8cm if the fella in the middle is your biggest. An estimate on the average size of the whole bunch - say most of them are around 1.3cm if you averaged them out, and what the size of the smallest (runt) is: say about 1 cm...

That type of thing :)

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