Larvae not surviving

[aku650]

Hi,
Long time lurker, I've learned so much from this forum. Everything is great, except for my larvae seems to vanish after a couple days. I've had my tank setup for about 16 months. I've been getting berried females about every 1to 2 months, with about 10-12 eggs hatching. The larvae hangs around for about 3-5 days and then completely disappears. I'm not sure whats going on.

Here's my water parameters:
Salinity:1.10
PH: 7.4
Nitrite:0
Nitrate:10-20
Ammonia:0-.25 (can't really tell if its a definite 0)
Temp: 69F-80F
No water changes just top offs with distilled water

Thanks for your help!

[Varanus]

How big is your tank? How many hiding places are there? Its possible the larva are simply metamorphosing and going into hiding until they have grown enough that you might not be able to tell them apart from smaller adults.

If they were dying one would think you would have seen a body or two but then I don't know yet how quickly supershrimp clean up carcasses (they or the snails certainly eat up their shed skins rapidly).

[mcdaney]

Show us your tank with a photo (or two)
Maybe we can come to a conclusion better?

[jonesinfershrimp]

temp swings and the trace amount of ammonia possibly. why such a swing in temps?

[Varanus]

temp swings and the trace amount of ammonia possibly. why such a swing in temps?

Aku should confirm, but I'm assuming those are gradual temperature shifts as seasons change and the temperature in the building proceeds to change as well.

[Mech]

why are your nitrates that high? that's probably the issue. If you are getting results like that then nitrites are being turned into nitrates, nitrites are coming from an ammonia source, You have somthing dead in the tank, over feeding etc.

are you using tap water?

[aku650]

Thank for the replies! I've attached a picture of my tank below. Its a 5 gallon tank with plenty of lava rock and 3 big chunks of coral rock. Varanus is right about the temperature changes. It fluctuates as the building temperature changes. I don't feed them anything, they just graze the walls and rocks. I'm using distilled water.

[Mech]

they look happy enough, if you cant sort the problem out i would advise a water change, say 30% or so to bring those nitrates down.

[KenCotigirl]

Very nice tank. I am a big fan of the black lava rock. Your pH of 7.4 seems low. Just checked mine, 8.2. Would not worry about nitrates. This is the end result of the nitogen cycle, algae food. When i check which I rarely do i only check pH, ammonia and nitrite. A couple pieces of coral or pieces of base rock would buffer the tank. I would wait for Mastafa to chime in before making any changes. Berried shrimp and floaters usually mean you are doing things correctly.

Ken

[KenCotigirl]

Oops. Missed the part where you wrote you had 3 chunks of coral rock. I await comments from Mustafa.

Ken

[Varanus]

The amount of hiding places created by the rocks, plus all the food from the algae certainly makes it seem possible to me that the babies simply are hiding out until they have grown a fair amount. Course by the same token the amount of spaces made by the rocks may explain why you haven't seen bodies if they are dying.

[mcdaney]

Nice! Seems like there's a lot of hiding places.
Once the larva are able to swim like the adults, they go into hiding to feel safe.
Food is already available to them in between the rocks/crevices.
My lone baby shrimp went missing for a few days before I saw him again, slightly grown up.
They're pretty tough to spot swimming around. Haha!
Hopefully you'll see them again soon.

[aku650]

Hi again. Thanks for all the fast responses. I'll just wait to see if I see baby shrimp. Do they just look like the larvae, but they swim horizontally? Or more like a super tiny adult?

[KenCotigirl]

Hello Aku ( from Samurai Jack) newly transformed shrimp look just like adults but about the size of larvae, about 3mm. They seem to swim for a day then may disappear for a few weeks. Then they act like adults, crawl on surfaces and occasionally swim.

Keep us updated.

Ken