what makes Astrea snails unhappy?

[DanStL]

THey are the only thing in my tank looking terrible, on their sides, not dead but hating life right now. Everything else is looking ok - ceriths, other inverts.

Are they a bell-weather for some particular issue? I'd rather not spend halloween testing everything if I can help it.

 

[~Flighty~]

What happens if you flip them over correctly? They sometimes just have trouble righting themselves in sand.

 

[NateHanson]

Astreas were created after an incomplete design process. Most importantly, they are unable to right themselves when they land on their sides.

It's possible that your snails aren't unhappy, just maladapted to a world with gravity.

To answer your question though, I've noticed snails are sensitive to salinity. What do you use to test salinity? Have you calibrated it against other types of devices? Swing-arm type hydrometers are notoriously inaccurate. IMO floating bulb hydrometers are perhaps the most accurate right out of the box (but a bit annoying to use, according to others). Refractometers seem to be the popular favorite for ease of use and accuracy.

 

[DanStL]

I didn't even try that, yesterday I found every single astrea (about 8 or so) all on their sides, some on rock. THis morning they were all still lying, with no signs of even trying to move. They all look sick. Wierd.

 

[DanStL]

Hmm. I think you may be right about salinity, or possible pH. those are my two guesses. I use a swingarm hydro, I know, I know, but I have used this one for years, and I dont go by the markings - i shoot for where NSW shows on it when I used to collect that.

Btw, going through all my old reef stuff, I have a salifert pH test kit but no instructions(not that I could ever read the thing anyways). Does anyone know the amount of drops to add to 5cc of water?

I'm looking across the wharf/downtown area now, and so far Salem is dead! I may make a quick break home to test this stuff...

 

[NateHanson]

I think NSW around here is lower s.g., like 1.020 or thereabouts.

 

[DanStL]

Yeah, it would test 1.021 on my hydro. I have always shot for that. Snail issue aside, is 1.020-1 not ideal?

 

[NateHanson]

I think most tropical reef-tank keepers would say 1.023-1.025 is a better target.

 

[dz6t]

Inverts like higher salinity. 1.021 is very low.

 

[scavdog]

Snails and the like are also very sensitive to stray voltage. Do you have a grounding probe?

 

[DanStL]

Well I went home and pH tested dead on 8.0, salinity still at 1.021, so I threw in a few handfuls of IO. I hope you guys are right, I would love to raise the salinity and problem solved.

Joe, interesting about the stray voltage. Everything (except seio for now) runs through a gfci. I couldn't test stray voltage with a multimeter could I?

I don't have a ground probe, but yeah I know I should get one

 

[scavdog]

All there is to know about stray voltage:

http://article.dphnet.com/cat-02/strayvoltages.shtml

 

[NateHanson]

You should be able to test for stray voltage by puting your multitester on VAC, and grounding the black probe on an outlet box or something, and putting the other probe in the water.

 

[naturebatslast]

I wouldn't trust your hydro until your compare it to reading done with a refractometer. Even though your shotting for a certain salinity value, you don't know how inaccurrate the hydro is, and if it's readings are too high or too low. You could be shooting for something that you don't want. Are there any members in your neck of the woods, maybe a LFS with a refractometer?

On a side note, talking recently with a prof at a marine sci program, he was stating that even though most refractometers are self correcting for temp, most self correctings only correct to 70 deg F, missing the extra ten or so degrees we need.

 

[DanStL]

Well it appears salinity was the issue

It's up to 1.024 now, and the snails are looking 80% better.

NBL, I had a refractometer a while back, used it once and sold it. It told me exactly what my floaty did, just was a lot harder to use it seems in this case I can't blame the machine, just the operator