2015 sometime
I recovered my first batch of typus larvae this evening. From mating to release ~15-18 days. Transferred to a slightly salty green water but not holding a lot of hope as the green water has crashed due to cold weather and doesn't look right. I've got another 4 berried females isolated so once each releases I'll set up a new coffee jar with a different water brew. The DAS are not going as well either (2 weeks in salt today) with high mortality which also points to the algal mix being wrong. I have a compound microscope now... hopefully some time over the break to look at the water!
Week old Caridina typus larvae taken through poor resolution kids microscope. I'm using the microscope to get a feel for the size of algae particles they might eat - the quality is too poor for much else but I have been able to rule out some of my green water sources as inappropriate because the algae was just too big. I'm guessing the algae needs to be in the 5-20 µm size range. I'm passing green water through a 50 µm mesh and the cells that get through are still way too big.
If many survive just a few more days it will mean they survived the first moult.... which is a big milestone. (the first three batches didn't make it! This one is showing promise)
I'm trying to rear them in seawater. I can see some larvae still in the "mother" tank clinging to the dirty glass - I'll leave them, and leave it dirty and see if any make it in the fresh water.
The main thing with these pics is the guts do not look empty... so I'm hoping that means they are eating.
The larvae are a little smaller than DAS larvae - about 1.5mm long. Yes living (until this one dried out on the slide) ... plenty more where he came from.
here is a picture of the green algae from my duck pond that is too big. Its the same higher magnification as the bottom two shrimp larvae pics ^ and as the larvae don't have well developed mouth parts yet they cant chew. - eating this algae would be like us trying to swallow apples whole.
Powdered spirulina from the health food shop has some smaller fragments that may be the right size but most are too big and settle out.
I think the larvae need to filter small particles as they don't have the mouthparts yet to chew on filaments.
01-03-15, 08:53 PM
Success at last after the tank developed its own suspended food supply (all artificial diets failed). Saw my first juveniles tonight. So ~5 weeks as planktonic larvae (in salt water) metamorphosing at ~3-4mm. Definitely swimming forwards like a shrimp (too fast to photograph). Similar development as for DAS but a little slower to develop and metamorphosing as smaller juveniles (may be a real difference or may just be less favourable conditions in the rearing tank). If they follow the same growth pattern as DAS they should grow much more quickly as little shrimps compared to the larvae.
01-03-15, 10:13 PM
I did look at some more local prepared foods - live cultures and phytoplankton pastes can be got from http://www.reefculture.com.au and if I'd had too many more failures I would have pulled the trigger on some. In the end I set up a variety of tanks and coffee jars with different water sources (+salt) and different lighting and let nature take its course until something bloomed in one of them. It looks like the Seachem product has similar algae - would provide more certainty if it works... next time perhaps!
Just to show how damn small juvenile Typus are despite 6 weeks growing as planktonic larvae. Settled DAS are twice the size.
This guy is approx. 2 months old.
Oh my. I've put a lot of very blurry phone camera photos up of shrimp larvae over the last few months. Tonight I re-acquainted myself with my old 7MP point and shoot camera (Canon A720) that as it turns out has a pretty good macro mode. I wish I could go back and start over. My C. typus released another bunch of larvae tonight. Tank was clear at 9pm and I found these just before midnight. Its impossible to get them all in focus but for the first time I snagged a photo of "0-Day" larvae where you can see they look like baby shrimp swimming vertically. Unfortunately I had to stop taking photos because they started to drift towards the filter and I wanted to catch them. Definitely room to improve further. More light will make for sharper exposures as these are hand held without flash in a dark room with only an LED torch on the tank (POS camera flash just reflects off the glass).
I cleaned the glass of a nearby fish tank and squeezed the cloth into my salt water C. typus lavae tank to add some algae and diatoms to the water as food for the planktonic shrimp larvae. The metamorphosed juvenile typus shrimp took that as a signal to "migrate upriver" and they congregated in the current of the air bubbler swimming madly "upstream" against the current. I only added a few drops of dirty rag "juice" to the tank but it must have smelt like "home".
Current is flowing left > right. Each baby shrimp is ~3-5mm long.
There are still some larvae that have yet to metamorphose into shrimplets, but I expect to migrate these into fresh water next week.
27-04-15, 04:42 PM
Today I put them into a bigger freshwater tank to grow (there were 10-15 slowpokes that either took a long time ... or died without ever metamorphosing).
So this marks the completion of my first C. typus breeding. They took 6-12 weeks as planktonic larvae in salt water before becoming juveniles, which is much slower than DAS (4-7 weeks).
Mortality was pretty horrendous this time around - at a guess 5% made it but I never counted the larvae.
6-12 weeks is a long time for a small unfiltered container and a second tank I had going with the same original water became colonised by blue-green algae and the water quality went to hell and the larvae perished.
Just sea water ~33g salt per litre but I use an el cheapo floating glass hydrometer that has a green stripe around the specific gravity of sea water. The time is probably right to do a few tests with 1/2, 2/3, 3/4 sea water etc.. again. Last time I tried everything died at 2/3 seawater... but that also happens when the algae mix isn't right so I need to run a bit of a sequence at the same time to resolve the salinity requirements better.
The problem with adding a filter is I want the micro particles for the shrimp to eat, so it has to be biomedia only - perhaps a fluid bed filter... but that would mean much bigger volume containers than I use now (2l coffee jars & 10l aquariums). I am playing around a bit with the air rates (=flow) a bit..but no clear winners yet.
11-06-15, 11:17 PM
Breeding typus is still a bit hit an miss for me. Last few batches trying lower salinities (~ 20ppt) didn't work very well (only a handful made it). The same algae cultures and salinities worked brilliantly for DAS at the same time. The Typus are smaller larvae so maybe the algae is too big. Now trying another run at higher salinity of 34ppt.
29-08-15, 06:52 PM
This is the first reproductive female that I've reared from hatching all the way to maturity. She's from the batch photographed ^^ 11-04-15. So now we know it takes approx 1 month for larvae to settle as juveniles and then approx 5 months to grow to sexual maturity.
And today I just completed migrating the second successful batch to go all the way through... 2nd from ~15 attempts. Ive had a few batches where only a handful survive and many where all died. This batch salinity ~24ppt, and temp 28C.
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