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I hope that works for you, definitely try the above green water too, if the cultivation works, its always best to have more algae strains for Moina.
Davy,
It will of course depend on the initial dose but if you keep it low, once a week should do. What is best is to grow high density culture of algae first, than let it sediment and pour out enough of the cultivation sulution to be able to dilute it in like 1:5 ratio with clear water. Growing the culture should not take long when you start with 10% of inoculum. Than put the aeration back in and wait for about 3 days. This way you are able to starve the algae from macro elements and it will make them prepare for “bad times”. What they do than, is they start to produce reserve substances like HUFAs and PUFAs and other lipids or other valuable nutrients that are not present in the algae cells to nearly such content when the algae have enough nutrition. Of course by limiting the macro elements, you cause the culture to stop the reproduction or it will reproduce much slower but you will get much more valuable algae and therefore much valuable Moina.
Thanks Peter,
The only problem is that I live in Czech Republic. I will try to talk them in to some less expensive, less expres shipping method first, becouse when I send killifish eggs to US it is much cheaper and it works fine, but even If I am not succesfull, buying from the US is probably still cheaper than buing from Germany. Becouse even with the shipping rate of 60.25 USD the 454g can is only 61 USD so its 120 bucks including shipping. The German one is 89€ without shipping. Seems like buying the big can is worth going for. If anyone is interested you can order it from here: http://www.brineshrimpdirect.com/c2/San-Francisco-Strain-Brine-Shrimp-Eggs-c24.htmlI completely agree with your statement Bernd, fish do not mind wether its 5.1 or 5.5 at least in most cases. For most species there is a safe range where eggs develop just fine. I was just talking about the case where the value shown by the pH meter would be under 6 and in fact in my particular case was 6 and a little higher which could even work for Paros, but would not work for other species I have. I also use my pH meter a lot as I prepare a lot of different types of water and some cultivation solutions for algae. I think it also depends on the type of electrode and type of device. I used to have very precise laboratory type devices couple years ago and I think the calibration lasted much longer, but I have obtained normal type stuff after it got old for the very exact reason you are mentioning. It realy does not matter if the pH is little higher or lower as long as you are within the range needed.
Also try to check your pH meter calibration, if your measurements are correct. Measuring in very low conductivity environments as we do with Paros will often lead to dilution of KCl solution in the electrode, so proper storing of the electrode in the 3M KCL storage solution and its frequent changes as well as frequent calibration should be matter of course. I have just checked my pH meter after approximately 3 weeks of frequent measuring and I was getting an error of about 0,4, so it seems like I have to check the calibration even more often. When measuring waters with higher volume of dissolved substances and higher pH, the calibration usually lasts much longer, at least for me.
I thought the paper could be interesting in some general stuff, like the mass cultivation in waste waters and factors that will most likely limit or stop asexual reproduction mainly. My Moina is most very likely either M.macrocopa or M.brachiata according to the typical pudlle occurance and the altitude of the locality. There are 5 species of Moina in Czech Republic but only these two reach this high population densities and occure in such environments. Other 3 are typical pond species.
Hello everyone. Here is very extensive paper on Moina and Daphnia that contains a lot of general information even though it is related to two particular species.
http://digital.library.adelaide.edu.au/dspace/bitstream/2440/62460/1/02whole.pdf
Ok, than going for larvae separation right after they get pigmented is clearly best. I already isolated what seems to be nicely multiplying Rotifera culture from one of the tanks, so hopefully I will have that culture next time. Rising the fry should be much easier for first couple days with this. It is evident that they are smaller than usual Brachionus but I was lazy to pull out a microscope so far and try to identify them.
Anyway thanks for help Bernd, now I probably know all the transferable information I needed and the time for experience is coming 🙂Thanks very much Bernd, I took away the females today, I think for the last time 😀 Taking out the larvae seems like the absolutely best option for any further care and for the option to not stress the parents and dismount the tanks all time. I am just wondering if labyrinth fish have some kind of imprinting of parental care and other behavior from parents for example like cichlids have? Or better question. Have you experienced artifically raised fish, especially males, be worse parents sometimes? Of course this question goes to everyone else too. As my imported Paros, even though these are their first spawns, seem to be great parents so far. Males present a great care for the first try and females are very responsibly guarding the teritory around the tank. It would be sad to ruin it with intensive methods like it has been done to other species over the decades of mass production. But if its not the problem, taking out larvae before they swim out of the cave seems to be great option. I have checked the clutches the newer clucthes and it seems this takes cca 4 days, so it should be even soon enough to not get in to any new eggs in the cave problem.
Taking out females sounds like the most reasonable option. I have not seen the mother to hunt the fry yet, but I can try leaving the parents in there in one of the other tanks and now just go for the safe way with what looks to be very lively fry from the strongest male and female I have. The clutch in there is worth saving and I should leave the male in there. Than I will probably put together another trio but use a bigger tank, it seems like the parsued female is kind of slim and still stressed out. I dont know how big tanks Bernd uses for such a set-up, but 12 liters may be to small. I hoped that making the tanks 35 cm long will help a bit, if like double the size is needed, it will not help.
So, now I have quite a lot freeswimming fry from the first clutch in the tank with trio. They stay close to cover but it seems, that with the very dark water and so many leaves and plants, they do not hide that much. They are very lively and actively hunting some organisms on the leaf litter. BUT of course the smaller female is hunting them. It looks like she is not very succesful untill now, they seem to be very fast and aware of danger, but still I am not happy about it and I feel somewhat emotionaly interested 😀 These are my first Paro fry. I was planning to remove the trio but when I checked the cave, there is of course another clutch in there. I also have another clutch from other pair developing for about 4 days and there may be another one in the third tank, becouse the male never shows up for feeding and just sometimes I can see him sticking the head out of the leaves at the back of the tank. It is evident that production of clutches is not a problem, so I am thinking about moving the male from the trio with his cave to another tank and see if he is able to hold the clutch anyways, becouse the first freeswimming fry is more valueble than the new clutch. What are your opinions? Or would you rather try and just move the breeders and try to raise the clucth without a male?
