I can't keep shrimp.

[uwphoto]

 

My JBJ 45 cube is a one year old. The tank has had minimal problems and I have enjoyed getting back into SW.

There has never been an issue with algae; at weekly 10 gal water changes there is barely any algae on the glass to clean. The system has a Tunze ATO and I use Red Sea additives, including ABC+ in the morning and Alk. in the evening.

Ph runs 8.1 to 8.2, Alk. ~8.4, Ca. 450 and Mg 1350. SpG 1026 and temp 78-79.

A mixed fairly basic coral collection has thrived with Frog Spawn growing and splitting and other LPS/SPS

growing as well.

The only coral loss has been to a Tailspot Blenny that ate a Chalice and Monti. A second monti was removed when he started eying it.

 

I have tried to keep (in succession) three shrimp: Peppermint, Blood Red Fire Shrimp and Skunk Cleaner.

Each started well, ate well, molted several times and grew in size. All would eat frozen food from my hand.

None of my fish bothered them (Tailspot, mated pair of Fire Dartfish, Citron Goby and juv. Possum Wrasse).

Each shrimp started to loose interest in food at about 3 months and then in a week or so died. Other inverts in the tank including 6 small hermit crabs and a Cowry have all done well for over 10 months.

I have no explanation for the demise of the Shrimp, but any suggestions would be appreciated, the first being, I guess, "don't keep shrimp".

 

[jbrfish]

That is interesting.....not being able to keep these shrimp. Could there have been metals the

shrimp were exposed too ?

 

We know they are very sensitive to quickly changing water conditions. I wonder if 10 gallon weekly water changes are rapidly changing the parameters too quickly too a point that the shrimp can't adapt.

 

Maybe iodine becomes depleted which these shrimp need to molt?

[uwphoto]

I did think about that and even measured before and after WC with no change noted. My daily dosing is so small that I doubt if there are major swings at those times.

Wouldn't Iodine get replaced with new water? (Although, I can't find the I content in Omega Sea.)

 

The base rock is Real Reef. Could it be leaching out a heavy metal. If so wouldn't that affect the crabs as well?

 

Thanks for the reply.

[BulkRate]

It might be worth getting a triton test done. Kinda spendy but if you want to rule out metals contamination, iodine levels or such getting a complete workup may at least tell you what you are dealing with in your particular case.

 

Most of the test we hobbyist's have access to & run are more to confirm what we already know/suspect or to allow for monitoring of dosages. I mean, that picture doesn't look like an unhappy reef by a longshot, and I'd have thought that least one of those shrimp should have done OK.

 

Just as a wild stab in the dark - do you dose H2O2 (peroxide) or have treated problem rocks with it w/o rinsing in holding water? Lysmata species are pretty sensitive to its presence.

[uwphoto]

Thanks BR.

The Real Reef Live Rock was cured for about a month when I first set up the tank last year. After that I started with all new water. It was at least a month after that when I tried my first shrimp.

I have never seen any type of nuisance algae and have been growing in the tank two types of macroalgae that I harvest about once a month; an in tank refugium.

This tank has been the easiest set up I have ever tried, but it is the smallest. I really enjoy it but have been perplexed by the shrimp issue.

The fish look great and are all great eaters.

Interestingly I have also tried a few Zoas and they just melted away, but that was early on.

 

The Triton test may be a good idea. But if there is something bad leaching into the water (BTW my SW is made with RO) it must be singular in effect to the shrimp.

[Mariaface]

Iodine, copper, quick addition of magnesium, quick rise in salinity, other heavy metals...

 

I'd say test your parameters before and after water changes, and before and after dosing. Alk shouldn't be changing more than 1dKH a day, and that change is best spread out over 24 hours. Mag shouldn't go up by more than 50-100ppm in a day, especially with sensitive inverts. Salinity, temp, same idea. That'll tell you whether things are fluctuating.

 

How often do you feed them? What do you do to clean your hands before putting them in the tank to feed frozen food?

 

Zoas might melt with low organics in the water. Do you test phosphate/nitrate? The effects of alk changes are more pronounced (at least in my experience) when nutrients are very low. If hardly anything grows on your glass, I'd look into that.

 

What's the TDS in your RO water? Can you get your hands on distilled or RO/DI water with 0TDS?

 

Is the tank 10 months old? Older? What do you do to maintain the sandbed? When's the last time you did a large (40%+) water change?

[uwphoto]

WC: RO/DI water with TDS meter that reads 0. (House water has a TDS of 150-180.) DI media changed ~4-6 weeks as crystals change color. Tank and new water SpG matched with refractometer that is calibrated. I cange ~20-25% weekly and have never done a larger volume change. Temp is matched as well. RODI water is made on Sat. salt added and mixed overnight with a circ. pump.

I have tested Ph, dKh, Ca++ and Mg++ in new water and the tank before and after WC and there are no measurable differences.

Tank has 0 nitrates and ~0.4 phos.. I use Red Sea test kits and have checked results at the LFS.

I have a very minimal sand bed. No sand to speak of under the base rock and maybe 1/2 inch in the front half of the tank. I feed all frozen foods using a dropper. The shrimp would come out to catch what they can. The five fish are not aggressive eaters. I would also target feed the shrimp several times a week using a long forceps. (They each became quite trained to this.) Mysis, Ref Frenzy...

Other than placing coral, etc I never put my hand in the tank but do wash hands and arms with lots of water beforehand.

 

I measure dKh 4-5 times/week and it is pretty steady at 8.4 to 8.6 and I have never measured a wide swing. Ca++ will vary between 430 and 460. Mg++ is pretty steady at 1350 as well. I don't add Mg++ as I am pretty sure it stays stable simply by the WCs.

Ca++ is added in the morning, as Red Sea ABC+ powder, 1/2 scoop on the filter pad in the back inflow chamber (JBL AIO) to be mixed as it goes to the tank. Alk. is added at night, Red Sea Foundation B as 4 ml. in the same way. These amounts were arrived at early on by testing drop in Ca++, Alk. and titrating what it took to match what was being "consumed". I have not felt a dosing pump was necessary with such small amounts. Ph is measured by probe and is 8.2 with lights on and 8.1 at night.

I would say the tank may be too "clean" for Zoas but not sure how that affects shrimp. The tank and fish do support Hermit Crabs and a Cowry. Also the coral to my eye has been thriving; the lps have grown and the sps have grown some are budding.

 

Heavy metals I have no idea but would they be selective in affecting just the shrimp?

Thanks for your input.

 

[Mariaface]

Shrimp can definitely be more sensitive to the metals, yes. With everything else going that smoothly, I'd definitely consider a Triton test

[uwphoto]

Thanks again.

I will be OOT for a week but will plan on testing the tank when I get back.

[uwphoto]

A follow up. Triton test shows no elevation in any unwanted Heavy Metals.

Macro elements are fine but for a mildly low potassium.

Iodine is modestly low and Barium is high.

 

Perhaps it is the low Iodine as the shrimp molted every 3-4 weeks.

[Clown79]

Its very odd. Do you acclimate them when you add them?

 

Molting is normal but when molting too often its a sign something isn't right.

 

I don't test iodine so i can't offer advice on it.

 

Do you run carbon, any other media?

[uwphoto]

I run Carbon and Chemipure.

I do acclimate for temp and drip. (I have to say I understand why temp might be important, but while I do drip the physiology doesn't make sense to me. What creature is going to acclimate to a change in salinity etc in an hour or so?)

 

I too don't understand it as the tank otherwise seems OK by water parameters.

[Clown79]

The only thing i drip acclimate is my shrimp. Apparently they are sensitive to swings.

[markalot]

I've never acclimated shrimp other than float for temperature.

 

I find it odd the tailspot would eat corals? This sends up all kinds of red flags because tailspots don't eat SPS. Mine lives below a monti cap and sometimes sits on it but the only thing it, and the last one I had, ever touched was a mushroom that got too close to it's hole.

 

The normal tailspot behavior is to bite and scrape at algae growing on surfaces, so perhaps you witnessed it eating algae in spots that were already dead?

 

So, assuming the tailspot is innocent, is it possible you have a bad hitchiker? Something you might be able to spot at night?

[Clown79]

Apparently its well known that blennies may nip at corals. Many have complained theirs ripped apart their zoas.

 

Many have peppermint shrimp that are model citizens yet many report them ripping corals apart..i'm one of them.

 

A hitchiker could be another explanation. I had a pistol hitchiker in my 55g and all my peppermints went missing and a lot of hermits too