problem poser......

[scubaboy60]

I'm writing in the hope that you may be able to help out.......

I desperately need sensible discussions on a problem I am facing and I need to pick your brains. I am stumped
at the moment, and could really use some help.

I am a long term reef keeper, been keeping marines for 20+ & reef for 15 or more, but I have a problem tank at the moment that I can't get a grip on...

The tank in question is a 5 * 2 * 2 1/2 foot reef with deep sand bed (crushed marble 000 chip) 3" deep closed loop circ system, (6000 lph) main return pump (6000 lph) (rainbow lifeguard quiet ones in both cases)
One 2,300 lph powerhead mounted close to surface of water.

Nutrient export via a Turboflotor 1000 skimmer ( on for ~14 hrs a day, off for a couple of hours while dosing supplements)

Bare sump no trickle with refugium

Tank has a 25 litre refugium fed from main outflow line from tank, & fuge has been lit 24 / 7 in past, but lights are off now.
(more on this later)

Tank is equipped with a Teco chiller, and runs at a constant 25 deg C.

Tank contains approx 125 kg liverock (270 lb)

Various corals ranging from sarcos to fungi's, duncanopsammias, scolymias, turbinarias, Morphs, and until recently a 14 year old tridacna (sadly departed but not related to this story directly) all doing well, but have had troubles in the past.

All Supplements used are Seachem, apart from one liquid coral food that I use from a different manufacturer.

Main aquarium lit by 2 * 250w 13,000 k halides Fuge is lit using a 24 watt 50 /50 actinic 10k PL power compact .

Tank usually runs at......

P.h. 8.0 - 8.2
sg 1.024
Kh 9 - 11 dkh
nh3 0.3 - 0.5 ( not 100% happy with the zero on the test kit though, Hagen ammonia kit in use)
No2 0
no3 Currently ~ 5ppm but sometimes as high as 10
Ca++ 420 today, targeting 450 as a rule.
PO4 under .5 ppm today.

Additives used:
Reef builder for Kh buffering Reef buffer when nescessary for P.h. (Not frequent)
Reef magnesium
Reef strontium Reef Iodide and Reef Plus
Magnesium, strontium & Iodide are not tested for currently, Seachem's basic dose rates are used.

W/changes of 175 litres (from 750) performed when NO3 is on the rise

So much for the overview, here's the problem.

Corals look good,
My fish keep dying.

Around 3 months ago, a sudden procession of deaths took out a number of fish that had been long term resident.
Zebrasoma flavescens
Lo vulpinus
//Synchiropus splendidus//
Amphiprion ocellaris ( over 8 years in captivity ) :'(
Rockhopper blenny (salarias sp.) * 3 in rapid succession

and also during the past few months all cucumbers (H. edulis predominantly but not exclusively) seem to have vanished, though a number of stromb shell are still active in turning over the sand bed.

I have saved one half of the clown pair which is currently in a hospital tank, but there is a comet grouper C. altivelis which due to difficulty in removal has sat in the tank apparently unaffected for the entire time.

I placed a sailfin tang Z. vellliferum into the tank a couple of weeks ago, Dead overnight
I placed a salarias blenny suspended in a restricted net so the animal could not eat anything from within the tank and would be protected from any predation (none suspected), Dead overnight

I left things for some time & have recently introduced another sailfin,, same result........

I have had a (i'm prety sure) Dinoflagellate bloom in the refugium on & off over the last few months but the lighting on the fuge has been off for a number of weeks, & there is no trace of anything macro or micro algae wise... (coralline growth in main tank is excellent by the way) I am getting a lot of Macro growth in the main tank currently as there is no fish to keep it under control.

I am running out of thoughts, and any steers in any direction would be greatly appreciated if you can spare the time.

The only products not Seachem used, are a coral food (limited use & not suspected) and the salt which is an australian brand called Aquasonic Ocean nature. all products are in use in a very successful micro reef setup not 15 feet from the main display.

Please help as I am running out of ideas and really hope for meaningful discussion & questions.

Thoughts, questions and speculations all gleefully accepted.



Thanks in advance,
John.

scubaboy60@hotmail.com

 

[Fish'InMN]

The only thing that pops straight to mind is low oxygen levels. This would be caused by not enough surface agitation (small factor) or inadequate skimming (not simply too small of a skimmer, but the skimmer doesn't receive enough of the tank water to process most of it in a given time period). Leaving the refugium lights off was undoubtedly needed to control the dino bloom, which in itself might use some O2?, but the lack of growing macro will also decrease (from previous time when macro WAS growing) O2 levels.

But I'm just throwing out ideas here, it may be something completely unrelated...

Marty

PS. You say you don't test Mg, but you use an additive that includes Mg. I've always been of the school of thought that "You shouldn't add what you cannot test for." Even if you're having success with a different tank with the same additives, it doesn't mean the levels in this tank are correct or in balance. High or low Mg levels could be affecting the fish, but the corals would certainly show signs of stress first... Either way, I would definitely get a Mg test kit to continue narrowing down your culprits.

 

[scubaboy60]

Help!

Help!

Thanks for the thoughts Marty,
but the O2 sats are almost definately not the issue. surface agitation is good, skimmer is appropriately sized, and though it only runs ~18 - 19 hrs a day, the times it is off are through the day.

The Magnesium measuring is an issue that I have been concerned with & I have just recieved an Mg kit which I will be using tomorrow...( requires distilled water which I don't have on hand....)

Things I can eliminate are cuke nuke The cukes have vanished, but I have had fish deaths as far apart as 2 months....

Disease:

From first fish down to last fish down in the initial period was around 9 days ( disease type time frame, I know but nothing visible)

Gap of two months before trying again.... all the while the grouper is still in the tank.....

three deaths within 24 hrs of introduction all on seperate days....

then a gap,
Then an intro & death within 24hrs....

Water changes have been done during this time....
Carbon has been added during this time......
etc. etc..

I'm thinking not disease due to quick kills....
Also the time spans between introductions...



I'm not having a win here....

Help!

 

[danceswithfish]

I am no pro, but is NH3 at 0.3 to 0.5 a tad high?

 

[Fish'InMN]

Glad to hear back from you, though I didn't think either of those would be the culprits when I posted, just some random thoughts.

Interestingly enough, Randy Holmes-Farley had a section in a recent online article about ammonia toxicity/lethality. Here are a few forum threads concerning such things, and a link to his article:
- Lethal or dangerous ammonia
- Ammonia Toxicity
- Major Problem Need Help
- I need help, my new fish keep dying
- Ammonia and the Reef Aquarium
- Reef Chemistry Articles

Out of curiosity, what is your acclimation procedure when adding new fish to your aquarium? This is one thing that was brought up in the fourth-linked thread that has not been discussed here.

Otherwise, keep reading and let me know what else to search for.


Marty

 

[artman18944]

my question concerns the cucumbers that you had in the tank. you said they have vanished. is it possible that they have died and may have released toxins that are killing your fish but not harming your inverts. have you run carbon or done any large water changes to see if that helps. just my .02

 

[scubaboy60]

Yes that had obviously occurred to me, and I have performed a number of big water changes & have added carbon.
A question I have of all is how long can H edulis toxins remain active??
Does anyone know? I would have thought only a couple of days is usual, even less with w/changes & carbon.....


Am I wrong on this??

The cukes vanished around the time the dino bloom was ocurring in the fuge, & I'm thinking that they reacted badly to it.

This has of course left the sand bed not well turned over, and I'm getting a firmish layer of sand developing on the top of the dsb. I have begun breaking through this by hand over the last few days, and not seen much in the way of bubbles arising from the sand..... (a clue maybe??)

I am planning to introduce a couple of cukes into the tank this w/end and see what happens, also am planning to introduce a fish into the refugium at some point in the near future as a test....
But thinking I might put some Purigen in first.

 

[dendro982]

If I understand right, most of the fish's death occurred within 24hr after their introduction in the tank? I had this only once, then changed supplier.
If other fish dies after long term in the tank, and after introduction of a new fish, which still alive - then could be some disease.

My pet peeve is a sand bed, accumulating wastes (had this problem, now BB), but you better check for yourself (DSB crash, DSB problems), I'm not imposing my opinion on you. Better to be informed.
I'm not a specialist in DSB, but will crushed marble chips work as DSB? I thought, that it should be very fine sand to function properly.
Try not to disturb DSB too much, before checking procedure of DSB removal (even if you will not remove it - just not to release toxins in the water column).

I would wait with cukes. BTW, are they able to sift through fine marble chips without damage for them?

Is skimmer produces a lot of dark colored skimmate? There is a very good thread about making skimmer use all it's potential: http://reefcentral.com/forums/showthread.php?s=&threadid=554786&perpage=25&pagenumber=1
You also may try (just to see what you get) to place some prefilter in sump, like 800 micron (~size of bridal veil fabric) Current USA filter media bag, the bigger one, to catch the big particles, that may accumulate in the sump and create the debris layer there.

Ammonia is too high - try to change test kit to API (saltwater kit), it's cheap and good. Sorry, can't figure the volume of your tank (metric mind), is the amount of LR at least 1 Lb per gal?
I had persistent ammonia and nitrites, when had not enough LR, but after adding sufficient amount of inert porous biomedia (Seachem Matrix, cheapest after CaribSea Reef Bones) - no problems.
BTW, my corals are reacting on the presence of ammonia - not dying, but feel not good.

Phosphates: you have no food left in the tank uneaten, I believe. Refugium should help with export of them, if moderate amount is produced, IMHE. What helps me best (in my 90g a lot of PO4 is produced due to heavy feeding) so far, is a let skimmer skim very wet after feeding and replace the loss of water by a new saltwater. But I have a side sump, this is a special case.

Magnesium and other additives: If you did that many years, and the deaths started only now, I don't see the problem. If not - better to stop any additives (except alkalinity and Ca), until testing. If you have a good coraline growth, you may have good magnesium levels. But better to check before adding.

I'm also using Seachem products, but Purogen wasn't particularly helpful (used it for slightly less that year). Water changes, skimming and carbon were much more efficient.