Invertebrates dying

Reef Doctor · 08/06/2012, 12:48 PM

Over the last month I have been having a major invertebrate die-off, and I can't figure out why. My tank is approx 1 yr old, and had three mithrax crabs, half a dozen porcelain crabs, hermits, tiger tail sea cucumber, 2 peppermint shrimp, and two small urchins. The mithrax are dead, less hermits, no cucs, a few porcelains left, one peppermint, and one urchin died, all within 4-6 wks.

My tank is 75 gal with 30 gal sump/refugium. ATI Sunpower 6x54 T5 lights (new lights a week ago.) Approx 150lbs live rock. Fish: 2 blue green chromis, clownfish pair, 2 bangaii, 1 flame angel, 1 foxface, 1 green clown goby. All fish are doing great.

Parameters:
Sp. gravity: 1.024
Nitrates: 8
pH: 8.0-8.3
mag: 1350+
Calc: 320
Alk: 4.0-4.5meq
Temp: 78 F

ANY IDEAS?

Maaka · 08/06/2012, 12:54 PM

Maybe a low amount of copper got into it. just a guess. But if your coral is not affected than it is probably not that.

moe458 · 08/06/2012, 12:59 PM

could be due to low calcium..i believe the calcium should be around 420-500.
Just my guess

_http://www.ehow.com/how_12128342_lower-calcium-aquarium.html

Reef Doctor · 08/06/2012, 01:02 PM

I've been working on raising my calcium, and am just getting my alkalinity up to where I want it. They were both low for awhile (I just started testing for them.) I was thinking maybe it was time to molt, and not enough calcium? It just seems strange they've been fine for a year, and then all of a sudden wham! Dead!

Reef Doctor · 08/06/2012, 03:10 PM

Anybody else have any ideas or solutions?

Heliman · 08/06/2012, 04:25 PM

Could be starvation...not much left over to eat after your fish have finished the food ?????...that's a lot of scavengers to keep healthy on leftovers !!!

Reef Doctor · 08/06/2012, 04:36 PM

Quote:

Originally Posted by Heliman

Could be starvation...not much left over to eat after your fish have finished the food ?????...that's a lot of scavengers to keep healthy on leftovers !!!

They were fed independently of all the fish, bits of shrimp, krill, spirulina, mysis, etc. So I don't think it was a food issue. I'd always drop extra food, and specifically feed the big guys directly. The weird thing is that they all died in such a short time duration. Nothing new has been added to the tank.

Mr. Bill · 08/06/2012, 05:41 PM

I doubt it's your cal... I don't test mine, but I do use regular Instant Ocean salt mix which is notoriously low and I don't dose, and I've never had any issues with inverts other than one turning rogue and killing the others.

What do you use to test your SG? Your reading is on the edge for inverts (I prefer to keep mine around 1.026). If you're using a hydrometer that's inaccurate or a refractometer that's out of calibration, your actual SG could be lower.

Also, how much and how fast have you increased your alk? Inverts are pretty sensitive to parameter swings.

08/06/2012, 12:48 PM	#1
Reef Doctor Registered Member Join Date: Jun 2011 Location: Arizona Posts: 141	Invertebrates dying Over the last month I have been having a major invertebrate die-off, and I can't figure out why. My tank is approx 1 yr old, and had three mithrax crabs, half a dozen porcelain crabs, hermits, tiger tail sea cucumber, 2 peppermint shrimp, and two small urchins. The mithrax are dead, less hermits, no cucs, a few porcelains left, one peppermint, and one urchin died, all within 4-6 wks. My tank is 75 gal with 30 gal sump/refugium. ATI Sunpower 6x54 T5 lights (new lights a week ago.) Approx 150lbs live rock. Fish: 2 blue green chromis, clownfish pair, 2 bangaii, 1 flame angel, 1 foxface, 1 green clown goby. All fish are doing great. Parameters: Sp. gravity: 1.024 Nitrates: 8 pH: 8.0-8.3 mag: 1350+ Calc: 320 Alk: 4.0-4.5meq Temp: 78 F ANY IDEAS?

08/06/2012, 05:41 PM	#8
Mr. Bill Native Floridian Join Date: Jul 2012 Location: Top of the Bay Posts: 256	I doubt it's your cal... I don't test mine, but I do use regular Instant Ocean salt mix which is notoriously low and I don't dose, and I've never had any issues with inverts other than one turning rogue and killing the others. What do you use to test your SG? Your reading is on the edge for inverts (I prefer to keep mine around 1.026). If you're using a hydrometer that's inaccurate or a refractometer that's out of calibration, your actual SG could be lower. Also, how much and how fast have you increased your alk? Inverts are pretty sensitive to parameter swings. Last edited by Mr. Bill; 08/06/2012 at 05:46 PM.

08/06/2012, 12:54 PM	#2
Maaka Registered Member Join Date: Feb 2012 Location: Lima, Ohio Posts: 329	Maybe a low amount of copper got into it. just a guess. But if your coral is not affected than it is probably not that.

08/06/2012, 12:59 PM	#3
moe458 Registered Member Join Date: Jun 2012 Location: Toronto, Ontario Posts: 312	could be due to low calcium..i believe the calcium should be around 420-500. Just my guess _http://www.ehow.com/how_12128342_lower-calcium-aquarium.html

08/06/2012, 01:02 PM	#4
Reef Doctor Registered Member Join Date: Jun 2011 Location: Arizona Posts: 141	I've been working on raising my calcium, and am just getting my alkalinity up to where I want it. They were both low for awhile (I just started testing for them.) I was thinking maybe it was time to molt, and not enough calcium? It just seems strange they've been fine for a year, and then all of a sudden wham! Dead!

08/06/2012, 03:10 PM	#5
Reef Doctor Registered Member Join Date: Jun 2011 Location: Arizona Posts: 141	Anybody else have any ideas or solutions?

08/06/2012, 04:25 PM	#6
Heliman Registered Member Join Date: Mar 2012 Location: Perth, Western Australia Posts: 266	Could be starvation...not much left over to eat after your fish have finished the food ?????...that's a lot of scavengers to keep healthy on leftovers !!!