Metabetaeus lohena larvae update

[Mustafa]

This is great! I actually don't mind daily updates...haha. Here's another piece of advice..if this "throw the larvae in a green water soup" method does not work, just try the "throw the green water into the larvae tank" method. But give this method a few more chances until all the problems surrounding it have been fixed. That jellyfish is a very interesting discovery. Did you start your green water culture with live algae or a semi-live algae paste? If it was live algae in a bottle, then a juvie jellyfish may have hitched a ride.

[KenCotigirl]

I will post a new picture this evening. All measurements are guesstimates. Newly released larvae about 2-3 mm. 3 day old larvae 4mm.
The algae was from live culture not paste. The jelly fish were in tank already before the algae arrived. I have seen small ones on many occasions but they were rarely more than one mm. The 4-5 mm size was quite a shock.

[Mustafa]

I think you should try to culture the jellyfish, too. They seem quite interesting.

[AndyH]

Hello!
Any update on the Metabetaeus lohena? I've read your three different discussions. I realize the discussions are from almost a year ago. Did you ever have any luck breeding them and keeping the larvae alive?
What about the little jelly fish?

[KenCotigirl]

The jelly fish I was not interested in culturing. I was worried they could eat the H. rubra larvae. Did not want a separate tank with jellies. The M. lohena is a long and frustrating story. After my last update I was having problems with my micro algae cultures. One I believe was contaminated with rotifers. After two days a rotifer population exploded and the micro algae was exhausted. No live larvae was found. Several other attempts with tetraselmis in addition to nanochloropsis failed due to crashing my algae. Then I finally kept my algae going but the M. lohena stopped breeding. So to bring you up to date I have a batch of nanochloropsis at 1.020 sg. and a batch of tetraselmis at 1.035 sg. I tore down my tank and put the shrimp in a new 5 gallon Mr. Aqua tank. I now have at least one M. lohena berried. My fingers are crossed. Will know more within the next ten days.

Ken

[AndyH]

Very interesting; Thanks for the update!

That's too bad about the jelly fish, but I understand where you're coming from. It'd be just another distraction at this point.

I'm sorry about the problems you were having with the micro algae. But it's exciting that another M. lohena is berried and that you're willing to give it another try.

[KenCotigirl]

Thank you. I am excited.

[Mustafa]

Thank you. I am excited.

Me, too. Let's hope it works out at some point.

[KenCotigirl]

It took longer than 10 days but I have an update. I found larvae this morning. It almost did not happen. I usually turn on the lure light before bed time say around 11pm. But last night I felt a head cold coming on and went to bed early. I also forgot to turn the light. At 6am when I took out the dog I realized my mistake and turned on the light. At 8 am I checked the trap and found larvae. Maybe a dozen. Maybe less. I put them in the tetraselmis mix with a salinity of 33. I did not take into account when I added the trap water the salinity would go down. It is now 27. I was shooting for full strength saltwater of 33 but will see what happens at 27. Maybe this was the reason for past failures. When using nanochloropsis I started at a salinity of 20 but never checked the algae/trap mix. It was probably 15-16 not full strength saltwater. I purchased a digital Milwaukee seawater refractometer after the new year. Very easy to use. I was using a hydrometer previously and will never go back. The meter is battery powered, digital desk top style not hand held. Cost 2x a good hand held and 3-4x a cheap hand held. I used a hand held refractometer for testing brix. Not as simple as the meter. I think they are worth the extra cost. Enough about the meter the larvae are still alive as of 9pm.

[KenCotigirl]

36 hours later and I can confirm at least two larvae are alive. They seem more active than my previous attempt. No pictures for now as these guys move too much and quickly. If there were more larvae I would remove some to take pictures but with only two I will not risk it.

[Mustafa]

Great! That's progress! If they are more active, that's a good sign. Keep the updates coming.

[KenCotigirl]

60 hour mark and they are still alive. I am feeling better and will try to take a picture tomorrow.

[KenCotigirl]

Another 24 hours and the larvae are still with us. 84 and counting. My first milestone will be six days, 60 hours from now. That was the longest I previously kept them. My hope is the higher salinity will make the difference. Feeding might be the next concern should they survive after six days. I did not plan on any feeding but the algae. Besides the tetraselmis there are clumps of algae I hope they can eat. My other hope is that they are advanced larvae and will become benthic after two or three weeks. Can't hurt to hope. While I have no new pictures they look very similar to the pictures from last April.

[KenCotigirl]

Another 24 hours and this time saw 5 larvae. Here is a very poor picture of a larvae about 2 mm. 108 hours old.

[KenCotigirl]

Another 24 hours and the larvae look healthy, I guess. They are still actively moving toward the light. They are 3mm in length. I am not saying they grew. I was just able to more accurately measure them. By this time tomorrow they will be over 6 days old and the longest I have kept them alive. I have gone back and read my previous journal which was incomplete and poorly detailed. Not much of a journal. I am not sure I am doing a better job now. Could someone read it and reproduce what I did? I am not sure I could! With that said my memory from last year is at the 5+ day mark the larvae were mostly found at or laying on the bottom of their tank. Not strongly attracted to light and only moving when disturbed. So if you trust my memory the larvae look in better shape than last year. Temperatures: room temp. Upper 60's to lower 70's. Top off with RO water. PH not tested neither was ammonia, nitrites or nitrates. Tested only salinity 27. Light 16 hours a day.