Questions On Larvae Tank

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rml6f4
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Questions On Larvae Tank

Post by rml6f4 » Sat Mar 31, 2018 5:38 pm

So one of my Straws is carrying eggs again, and against my better judgement I’m considering an attempt at raising the offspring. I skimmed through the breeding stickies and wanted to get an opinion on a larvae tank setup.

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So I have a ten gallon tank full of water, a heater with a thermostat in the main water area to heat the main water to 78F, and separate glass jars. I plan on setting up some split bubbler lines to go into each jar.

Do you guys think mason jars with daily water changes would be large enough to support the larvae?

For the water that goes in the jars, is it just Tap water + dechlorinator + Instant Ocean with the water heated to 78F? Is there anything else special the jar water needs? What do I need to test the water for?

Oh and here’s the eggs!
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Re: Questions On Larvae Tank

Post by Moonlightdreams » Sat Mar 31, 2018 7:38 pm

I know nothing about zoea, but that's a gorgeous Straw! :D
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Re: Questions On Larvae Tank

Post by aussieJJDude » Sun Apr 01, 2018 9:00 am

It may support the larvae, especially with feeding! ;) which leads me to my question, what are you thinking of feeding them?


The zoea can be incredibly cannibalistic, so be prepared to lose a few if they do predate on eachother.

Edit: also if you do split the lines, get a valve on each line you have so you can balance out the flow in each jar. Also consider increasing the amount of jars, which will also help with water quality.
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Re: Questions On Larvae Tank

Post by rml6f4 » Sun Apr 01, 2018 1:33 pm

aussieJJDude wrote:It may support the larvae, especially with feeding! ;) which leads me to my question, what are you thinking of feeding them?


The zoea can be incredibly cannibalistic, so be prepared to lose a few if they do predate on eachother.

Edit: also if you do split the lines, get a valve on each line you have so you can balance out the flow in each jar. Also consider increasing the amount of jars, which will also help with water quality.
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From reading Curlz docs, I was going to feed:
1) Live phytoplankton (eBay)
2) Instant Baby Brine Shrimp (Ocean Nutrition)
3) Decapsulated Brine Shrimp Eggs (Aquatic Foods Inc)

I’m considering investing in an automatic feeder for the decapsulated eggs for when I’m at work.

I bought a 4-way air control and check valve combo. I haven’t set it up yet, but hopefully it works.

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Re: Questions On Larvae Tank

Post by aussieJJDude » Sun Apr 01, 2018 6:18 pm

Sounds like you have everything under control, I look forward to hearing process updates.

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Re: Questions On Larvae Tank

Post by GotButterflies » Mon Apr 02, 2018 8:31 am

First of all...CONGRATULATIONS!!!!

I would prepare more mason jars. So you have more water for the water changes! This way the water will be ready when you need it - same temp/same salinity. Always keep the water moving. I recommend a powerhead. That is what I used. You use it outside of the jars, this keeps the heat going around the aquarium. :) Mlakers and I both had zoea last year!! This year I have a kreisel tank made if my hermits breed again! Anyways...we both fed ours brine shrimp eggs, spirulina, chlorella, and Hikari first bites. Don't over feed!

Good luck!

Honestly, instead of the automatic feeder, just put eggs in - they will eat the eggs, and whatever eggs they don't eat, they will hatch! Then the zoea will have brine to eat! :) Also - phytoplankton is great! :)
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Re: Questions On Larvae Tank

Post by rml6f4 » Mon Apr 02, 2018 10:49 am

GotButterflies wrote:First of all...CONGRATULATIONS!!!!

I would prepare more mason jars. So you have more water for the water changes! This way the water will be ready when you need it - same temp/same salinity. Always keep the water moving. I recommend a powerhead. That is what I used. You use it outside of the jars, this keeps the heat going around the aquarium. :) Mlakers and I both had zoea last year!! This year I have a kreisel tank made if my hermits breed again! Anyways...we both fed ours brine shrimp eggs, spirulina, chlorella, and Hikari first bites. Don't over feed!

Good luck!

Honestly, instead of the automatic feeder, just put eggs in - they will eat the eggs, and whatever eggs they don't eat, they will hatch! Then the zoea will have brine to eat! :) Also - phytoplankton is great! :)
Thanks! Do you have any suggestions for the number of jars? Right now I’m planning on using four for the zoea and am using the large vase for a water change backup. Other than that I was just going to mix warm/cold tap in a separate container until I get it to the correct temperature.

I’m pretty sure I have a power head in my random accumulation of aquarium stuff, so I’ll have to see about installing that.

You think even with being gone for work ~9 hours a day they’ll be ok without being fed that long? And putting the eggs in the zoea jars instead of hatching them in separate jars won’t dirty up the water too much?

Also, do you plan on testing your water for anything?

Sorry for all of the questions. I have zero aquarium experience so this is all new to me!

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Re: Questions On Larvae Tank

Post by GotButterflies » Mon Apr 02, 2018 3:26 pm

I think I had around 6 or 7 mason jars, and then I also had two gallon jugs filled with msw constantly. You will go through a lot of water. If I remember correctly the first day or two they will eat their egg sac, so you don't feed them. Also, the zoea are very sensitive - I don't recommend anything other than the water that is the same temperature as the aquarium water. Always have it ready! :) I'm tagging @mlakers and @renroc - both will have valuable input. I used Prime water conditioner - didn't ever test the water for anything. I do have YEARS of aquarium hobby experience under my belt, so that helped me. :) Good luck - we are here for you! :) Always keep the zoea moving with a bubbler! :)

Edit: actually I used a goldfish bowl and 5 mason jars. :)
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Re: Questions On Larvae Tank

Post by rml6f4 » Mon Apr 02, 2018 4:06 pm

@GotButterflies

You’ve been so helpful! Thank you so much!

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Re: Questions On Larvae Tank

Post by GotButterflies » Tue Apr 03, 2018 2:24 pm

Yw! :)


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Re: Questions On Larvae Tank

Post by mlakers » Sun Apr 15, 2018 11:07 am

Yes! Everything @GotButterflies says is consistent with what I did. I was able to get a few (three-ish?) to megalopa stage, but none took shells. However mine were PPs and they do go through one more larval stage than strawberries, so that should shorten your length of time pre-megalopa, which will help. I second that prime directive of "DO NOT overfeed." In the mason jars, waste is going to be your single-biggest enemy, especially on days when they shed and move into a new larval stage. The water gets fouled really quickly on those days, so just watch for that. Honestly, as awful as it sounds, given that you are going to be gone 9 hours every day, I would feed less and let them cannibalize more. You'll likely have thousands of zoeae, and it will be much cleaner in the long run. (I know, I know, but it's a survival strategy in the wild and isn't quite as barbaric as we humans tend to think it is. If one individual lays thousands of eggs hoping to get a handful to survive, then the "siblings" that become a meal are also helping that handful to survive and pass on the genes.) And if you can stand to do it, don't put 500 in each jar--put more like 50 in each jar. I found that I couldn't NOT try to save them all and it definitely worked against me and against the zoeae. Fewer per jar do better by far. (THIS SHOULD BE THE HERMIT BREEDER'S MANTRA!) I had this confirmed, inadvertently, after I had heavy losses in one jar and didn't add any more. That jar BY FAR fared the best.

I've been making and selling pottery crab dishes to raise money for a new breeding attempt this year (hoping my crabs cooperate!) and as a result, I have had the funds to buy a bunch of new stuff, including a 20-gallon breeder tank that I am making into a side-by-side double kreisel (I'm too anxiety-prone to put all my hopes into one container), a UV light, reef crystals IO, some new foods to try (copepods, phytoplankton, and marine snow), some new cell-phone camera lenses to help document the attempt, and I'll probably do some mason jars and a small hex tank, too, if I have an excess of larvae like last time. I'd rather experiment with survival rates in other containers than flush them down the drain--everything we learn helps to increase the knowledge base which helps future attempts. Good luck!!

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Re: Questions On Larvae Tank

Post by mlakers » Sun Apr 15, 2018 11:21 am

Oh, also, I believe most people doing this have found that a slightly warmer water temperature actually encourages them to move through the stages more quickly with no ill effects. There is some disagreement on the temperature issue, I know, so it's ultimately up to you, but I am planning to make 78 a minimum temp, not max. Last attempt I kept mine at 83-degrees Fahrenheit (researched summer Caribbean water temps to get that number) and they seemed to do okay, especially in the earliest stages. When I had to be away over a long weekend, I turned it down to 80 degrees to sort of slow down their bodily processes and put their development on hold until I could get back to a regular feeding and cleaning schedule.

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Re: Questions On Larvae Tank

Post by rml6f4 » Mon Apr 16, 2018 1:53 pm

mlakers wrote: Honestly, as awful as it sounds, given that you are going to be gone 9 hours every day, I would feed less and let them cannibalize more. You'll likely have thousands of zoeae, and it will be much cleaner in the long run. And if you can stand to do it, don't put 500 in each jar--put more like 50 in each jar.
I mean, I gotta do what I gotta do. Best-case scenario only a few are going to survive anyways. I’d just be worried they all flat out starve instead of feeding on each other. Thanks for all of your suggestions though, they’re pretty consistent with what I’ve been reading, which makes me a little more confident.

I checked the eggs last night and they have a slight tinge of gray and I believe I saw some little eyes developing. Yikes! Right now my main panic is actually catching her laying them and getting them to the raising tank on time. My normal pool definitely would not keep them alive for long.

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Re: Questions On Larvae Tank

Post by rml6f4 » Mon Apr 23, 2018 12:10 am

Still waiting! Even Daddy Crab has started waiting by the pool with Mama Crab. Eggs have been light gray for a few days.

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Re: Questions On Larvae Tank

Post by GotButterflies » Mon Apr 23, 2018 7:12 am

I also kept my zoeae at warmer temps, and used a uvb bulb on them.


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