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How to: Clean, easy and highly nutritious greenwater culture for Daphnia and Moina.

I have leaf litter in my indoor jars, ready to go. Ostracods have already appeared there. I just haven’t been able to expand the moina after hatching. They live around a week, but haven’t taken off fast enough to transfer them to the larger container. I think partly I might be killing them when adding chlorella/fish mix.

Have you tested the Chlorella culture for ammonia?

Also what water are you keeping the Moina in? Mine always similarly died if I kept them in the RO water (with a dash of potassium carbonate to ensure a positive pH) that I hatched them in - but my main growing on tank was tap water based, so plenty of calcium, which I suspect they need in order to grow their carapace.
 
Have you tested the Chlorella culture for ammonia?
I haven’t yet lowered the fix mix such that the supernatanr isn’t brown. But I could measure the water in the starter culture.

Also what water are you keeping the Moina in? Mine always similarly died if I kept them in the RO water (with a dash of potassium carbonate to ensure a positive pH) that I hatched them in - but my main growing on tank was tap water based, so plenty of calcium, which I suspect they need in order to grow their carapace.
I make 100 TDS water for my betta tank with RODI + Equilibrium, about GH 3. I use that for the moina hatch. My tap water is soft and has chloramine in it, so I’d need to add sodium thiosulfate, which isn’t good for the moina either. I could make a third kind of water, I guess, if that’s recommended.
 
I haven’t yet lowered the fix mix such that the supernatanr isn’t brown. But I could measure the water in the starter culture.

Oh, if its still brown, it's likely to still have plenty of ammonia in it - too early to use it for feeding.

I make 100 TDS water for my betta tank with RODI + Equilibrium, about GH 3.

I'm sure that should be plenty.
 
It may do, but the Biobizz Fishmix contains a lot of ammonia already out of the bottle. I had issues feeding the chlorella culture to the moina when there was too much ammonia still in there, and it killed the Moina culture. I tried adding additional micros and PO4 as I suspected that the culture ended up bottoming out one nutrient or another and stalled before all the ammonia had been consumed. I think starting with half the dose originally advised by @louis_last is a good starting point, and even less may be sufficient, and maybe adding a little PO4 and micros half way through the culturing time.
FYI I found that half the dose of fish mix was still too much, so instead of continuing to titrate down, I now just dip my pipette in the fish mix and use that amount when I passage the culture. Indoor culture does require a lot of input, as I need to ensure I have lots of chlorella available when the moina are in log phase. Otherwise, they just keep dwindling back. Close to giving up on these, but it would be nice to have another live food other than artemia nauplii.
 
FYI I found that half the dose of fish mix was still too much, so instead of continuing to titrate down, I now just dip my pipette in the fish mix and use that amount when I passage the culture. Indoor culture does require a lot of input, as I need to ensure I have lots of chlorella available when the moina are in log phase. Otherwise, they just keep dwindling back. Close to giving up on these, but it would be nice to have another live food other than artemia nauplii.

Do you have a grindal worm culture? Easiest there is!
 
Do you have a grindal worm culture? Easiest there is!
Ha! Just replied to you on another thread about them. My fast growing cultures (scouring pads) crash when I'm away for a week. The slow growing culture (coir) I can't keep the invaders out. Also, my paros don't like them, and many are too large for the Boraras. At the moment, they're most suitable for my Betta imbellis, who to be fair, adores them. He's only one fish, though, and he'll eat anything.
 
Also, my paros don't like them, and many are too large for the Boraras.

That's surprising to read - I'm not sure many, if any, of my grindal worms are too large for my Boraras (Brigittae). I wonder if there are different sub species? (@dw1305 might know?)

Close to giving up on these, but it would be nice to have another live food other than artemia nauplii.

Yes, I gave up on the indoor culture, it's far too much effort. The outdoor cultures worked better but I wasn't able to source any Moina this year. Had lots of success with Daphnia in the outside tubs this year, but I need to grade them as the adults really are too large even for my Chocolates.

My Dero worm cultures are still running too - they are still a bit labour intensive compared to the grindal worms requiring water changes 2-3 times a week, not to mention they stink rotten when you open the tubs up. My fish also still seem a little perturbed about the fact that the worms can swim upwards in the water column.
 
Hi all,
That's surprising to read - I'm not sure many, if any, of my grindal worms are too large for my Boraras (Brigittae). I wonder if there are different sub species? (@dw1305 might know?)
Yes, I haven't kept Parosphromenus for a while, but I had P. "Bintan" and <"they were really keen on Grindal worms">, same for Boraras briggitae. Parosphromenus weren't keen on Daphnia, but other than that they had a go at all small live food.

I don't know if it is a general finding, but B. briggitae apparently eat pretty much anything, flake, small pellets and any live food.

cheers Darrel
 
I wonder if there are different sub species? (@dw1305 might know?)
Hi all,

Yes, I haven't kept Parosphromenus for a while, but I had P. "Bintan" and <"they were really keen on Grindal worms">, same for Boraras briggitae. Parosphromenus weren't keen on Daphnia, but other than that they had a go at all small live food.

I don't know if it is a general finding, but B. briggitae apparently eat pretty much anything, flake, small pellets and any live food.

cheers Darrel

Thanks Darrel - I meant different sub-species of Gindal worms where one might have larger average sizes than another?
 
Yes, I haven't kept Parosphromenus for a while, but I had P. "Bintan" and <"they were really keen on Grindal worms">, same for Boraras briggitae. Parosphromenus weren't keen on Daphnia, but other than that they had a go at all small live food.

I don't know if it is a general finding, but B. briggitae apparently eat pretty much anything, flake, small pellets and any live food.
My Boraras brigittae do love the grindal worms, but I think the smaller, younger worms are most appropriate. I can roughly grade them and pipet up the small ones, but usually a few larger ones get in there. I find those are not easy for a small fish to eat. The fish might swim around with half a worm sticking out of its mouth for about 10 seconds before it can choke the rest down. My fear is that this would lead to overfeeding or intestinal blockage. My B. brigittae do well on artemia. They'll take crushed bug bites mixed with artemia if I train them to, but I find that's more work than artemia alone, which I have to hatch anyway for the paros.

Most species of Parosphromenus take grindal worms readily. Mine took them cautiously as their first food after transport, so they hadn't eaten for a couple weeks. Since introducing artemia nauplii, they just spit out the worms. I've tried many things, including fasting them for a few days and feeding the worms first, same result. When I brought it up with The Parosphromenus Project folks, the rep from Great Britain said he'd observed the same with the species that I have (Phoenicurus) and considers altering the guidance for ideal foods based on that experience. It's a tough food to eliminate, as there aren't a ton of easy live food options for small mouthed fish that are mostly benthopelagic.
 
Interesting catching up on the results from people experimenting with this. I've begun experimenting with moina culture again and I'm pursuing some different angles that might be of interest. I was able to get good results with the chlorella but as has been noticed my protocol was fairly imprecise and there are some pitfalls to using the fish mix, for me the biggest of these was contamination of the chlorella cultures with other photosynthetic organisms - in fact my chlorella cultures were ultimately overtaken by some other phytoplankton that actually seemed unable to support cultures of moina but was incredibly productive for ceriodaphnia which were even smaller. I can't remember if I ever posted it to this thread but I also found it was possible to make a gel food for shrimp/ottocinclus etc. using living chlorella algae by flocculating the algae cultures using chitosan in order to seperate the algal cells for suspension in agar or geletin and in theory the algae retains FAR more of its nutrional value this way as compared to drying.
I've found some improvements to the moina and yeast method that seem to reduce the chances of cultures crashing but are unfortunately slightly more effort intensive. It seems that even when feeding yeast sparingly it often settles out of suspension and rapidly fouls the water. I believe this is at least partly due to the fact that packets of dried yeast contain a lot of completely dead yeast that won't reactivate, this isn't a problem when making bread as only a little viable yeast is necessary to get things going, but makes it more prone to fouling the water in a moina culture.
Since starting this thread I've learned that people cultuing moina in asia actually add sugar to the mix in order to multiply the living yeast and emphasise the importance of filtering the mixture to remove clumped dead yeast cells before feeding the moina and so far this does seem to be delivering better results. I'm also now using a large reptile heat mat to heat the cultures from beneath rather than small aquarium heaters in the culture water and this seems to help by creating a constant convection current that keeps foodstuffs in suspension longer and prevent them settling out before the moina can eat them. In theory an aquarium heater does the same thing but is more efficient and so only kicks on when the water temperature drops below a set point - the reptile heat mat is less efficient at heating the water and so stays on all the time creating a permanent and very easily observable convection current.
In addition to this I've also found that overcooked carrot is a viable food for moina and perhaps the least effort intensive method of production. You can simply boil a slice of carrot for half an hour or so and then add it to water, keep it warm and once the water appears slightly cloudy (after approx 48 hours depending on temperature) add a few moina. There's no need for any supplemental feeding after this, the carrot feeds bacteria in the water as it continues to break down which in turn feeds the moina. This method may be slightly less productive than others but has the advantage of requiring very little input after setup. For feeding a 10 gal tank you can rotate between two 32oz plastic cups innoculating a new culture with a few moina each week or so and being able to feed a decent amount of moina from the active culture twice in roughly the same period. I also notice that moina produced in this way have a noticeable orange colour so it may be the case that there's caratenoid pigments which could be passed onto your fish.
What I'm going to be experimenting with now is feeding moina with fish oil emulsions created using polysorbate as an emulsification agent and liposomes containing fish oil bound within an artificial "cell" of phospholipids in the form of soya/sunflower Lecithin. I have found references to cladocerans being both enriched and cultured exclusively on each in scientific literature.
I'm particularly optimistic about the fish oil liposomes that I intend to produce using an ultrasonic jewellery cleaner. The reason I believe this method has some interesting potential is that in theory the liposomes possess a charge that keeps them permanently suspended in the water and also evenly distributed throughout. I also believe they may foul the water less quickly than yeast.
If this seems to work well then it could be the best solution as large batches of the liposomally encapsulated fish oil can be prepared and stored in the fridge for use as needed. I've also seen a product marketed for human consumption called liposomal supergreens or something like that which seemed to be a preparation of liposomally encapuslated chlorophyll extract from alfalfa. If I can figure out how to manufacture something similar then it may also allow for the preparation of a viable moina/daphnia food using dried algae and such that has the same advantages of not settling out and remaining evenly distributed through the water column.
I'll update this thread if I get any promising results.
 
Thanks for your work on this protocol! It took a bit of tweaking to find the right conditions to reproduce with my hands, but I've been consistently growing chlorella and moina indoors for a few months now. Because I can't use sterile technique at home, I have no idea if it's actually chlorella or some other mix of phytoplankon. But it seems to work. Couple experiments I'm interested in:
  1. Trying your carrot method. Growing chlorella is easy enough, but that sounds even easier.
  2. Co-culturing the moina with copepods. I've heard mixed results from others:
    • Many say they live together just fine.
    • Some hypothesize that Cyclops spp are predatory to the young moina. Others argue that Cyclops are simply hardier, and thus more likely to survive if the moina crash.
    • Most say they have difficulty growing out dense copepod cultures when they try to do so intentionally--that they only thrive during happy accidents.
Cheers
 
I've been doing this as a way to keep a nice supply of daphnia, as opposed to moina, over winter and so far I've been happily supplying daphnia to 6 tanks for several months. I'm very imprecise in my method and I wonder if daphnia is more tolerant to poor conditions than moina?
 
Thanks for your work on this protocol! It took a bit of tweaking to find the right conditions to reproduce with my hands, but I've been consistently growing chlorella and moina indoors for a few months now. Because I can't use sterile technique at home, I have no idea if it's actually chlorella or some other mix of phytoplankon. But it seems to work. Couple experiments I'm interested in:
  1. Trying your carrot method. Growing chlorella is easy enough, but that sounds even easier.
  2. Co-culturing the moina with copepods. I've heard mixed results from others:
    • Many say they live together just fine.
    • Some hypothesize that Cyclops spp are predatory to the young moina. Others argue that Cyclops are simply hardier, and thus more likely to survive if the moina crash.
    • Most say they have difficulty growing out dense copepod cultures when they try to do so intentionally--that they only thrive during happy accidents.
Cheers
I've had plenty of copepods in most of my moina cultures as a consequence of using tank water for changes in the moina cultures but they don't seem to ever reach great numbers. I've never been able to culture freshwater copepods in large numbers but there are so many different species that it's always worth a shot. In theory some of them will pray on moina and reduce the productivity of a culture but I've never found this to be a problem. I've found rotifers to be more of an issue as they reproduce even faster than the moina and outcompete them for food.
I'll upload a video of a carrot culture for you later today. Something that surprised me with this method is that once the moina reach their adult size they will actually cluster clinging to and grazing from the surface of the decaying carrot in addition to filtering particles from the water as they swim. This presumably explains their distinct orange/yellow colouration but is hard to photograph as shining a light on them always causes them to start swarming.
 
Thanks for your work on this protocol! It took a bit of tweaking to find the right conditions to reproduce with my hands, but I've been consistently growing chlorella and moina indoors for a few months now. Because I can't use sterile technique at home, I have no idea if it's actually chlorella or some other mix of phytoplankon. But it seems to work. Couple experiments I'm interested in:
  1. Trying your carrot method. Growing chlorella is easy enough, but that sounds even easier.
  2. Co-culturing the moina with copepods. I've heard mixed results from others:
    • Many say they live together just fine.
    • Some hypothesize that Cyclops spp are predatory to the young moina. Others argue that Cyclops are simply hardier, and thus more likely to survive if the moina crash.
    • Most say they have difficulty growing out dense copepod cultures when they try to do so intentionally--that they only thrive during happy accidents.
Cheers
Here's a video of one of the carrot cultures. It's been about four and a half days since I added roughly 20 moina.

 
I've been doing this as a way to keep a nice supply of daphnia, as opposed to moina, over winter and so far I've been happily supplying daphnia to 6 tanks for several months. I'm very imprecise in my method and I wonder if daphnia is more tolerant to poor conditions than moina?
In theory the opposite is true and moina are supposed to be much more tolerant of poor water conditions than the common daphnia species but there's so many variables to account for in any comparison. I think it's probably easier to maintain a stable daphnia culture because they tend to reproduce more slowly whereas moina can double in number every couple of days under optimum conditions.
 
Here's a video of one of the carrot cultures. It's been about four and a half days since I added roughly 20 moina.
Sounds like you run these 32oz cultures to saturation and then start new each week. Have you tried adding less carrot and leaving it in a longer-term culture, or is that just asking for trouble?
 
In theory the opposite is true and moina are supposed to be much more tolerant of poor water conditions than the common daphnia species but there's so many variables to account for in any comparison. I think it's probably easier to maintain a stable daphnia culture because they tend to reproduce more slowly whereas moina can double in number every couple of days under optimum conditions.
That's interesting as I've not actually changed the water in their tank - ever.
 
Sounds like you run these 32oz cultures to saturation and then start new each week. Have you tried adding less carrot and leaving it in a longer-term culture, or is that just asking for trouble?
I'm still experimenting and fine tuning. There's obviously got to be an optimum ratio of carrot to water that would produce the best results. There may be better vegetables to use too. It was someone in Asia who tipped me off to this and said that they start all their cultures this way, only transitioning to yeast feeding once they are in much larger culture vessels. They said 1cm cubed of carrot or potato per liter of water, I went with carrot because it contains more sugar but sweet potato might be interesting to experiment with too.
How long you boil the carrot for before you add it to the water is a factor too as it will impact how quickly it breaks down.
I should do several side by side started with the same number of adult moina. Boiled whole carrot chunk, Carrot shavings that should break down faster, Raw carrot, and one with carrot but no moina in order to observe at what stage the cloudiness of the water peaks.
It's not obvious to me why a big chunk of rotting carrot doesn't kill off the moina but a relatively small amount of dead yeast seems to.
 
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