Just lost a great fish, HELP!

[ogre]

My Green Wolf Eel just died for no apparent reason. Water quality is great, except for high Nitrates. That has been a constant battle for many months so I tend to rule that out. I think it has to do with the food... He was always a very healthy eater. On a couple of occasions he did go on hunger strikes until I introduced something new. Started with Silversides, then Krill, then Tuna steak strips, lastly Hadock strips. He would not eat scallops,crab, or sardines. He seemed a little blotted when I pulled him out just now. The Lion is acting same as always. Any thoughts, Anyone?

 

[prime311]

Any other odd changes? Temperature, pH or anything like that?

 

[ogre]

No. He has been acting the same as always except when I fed them yesterday he was not interested and just stayed in his cave and seemed to be breathing hard. I new something was up but it just happened real fast. Is feedind him Tuna or Hadock bad?

 

[prime311]

Not that I'm aware of. Maybe take your water to an lfs and have them double check your results. Those test kits can go bad.

 

[ogre]

New test kit, actually just tested yesterday and as has been the case for 6mo now the readings are the same. Everything is at zero but Nitrates,Salinity 1.018. I just can't imagine that it would take 6mo for water quality to cause a death,at least not with tuff fish like a Wolf Eel. The Lion is fine... today that is.

 

[redman1221]

Originally Posted by ogre
http:///forum/post/2783401
New test kit, actually just tested yesterday and as has been the case for 6mo now the readings are the same. Everything is at zero but Nitrates,Salinity 1.018. I just can't imagine that it would take 6mo for water quality to cause a death,at least not with tuff fish like a Wolf Eel. The Lion is fine... today that is.
I would raise the salinity up to 1.023 at least, yours is a little low.

 

[srfisher17]

Originally Posted by redman1221
http:///forum/post/2783542
I would raise the salinity up to 1.023 at least, yours is a little low.
I may be in the minority; but I think fish (not inverts) thrive at a lower SG. I believe most online dealers and wholesalers keep fish at a lower SG than we realize. Before LR, reefs and inverts were so popular, many hobbiests kept fish as low as 1.017. Less stress on the fish ( lower SG water= less inward water pressure on the fish, sounds weird, I know) and fewer parasites. I'm convinced that fish are actually more active at a lower SG. Its easier to swim in lighter water. I believe there are a few others on this forum with the same opinion.
As to the eel; nitrates are seldom a problem for fish. Unfortunately, (IMO) the cause of most fish deaths are never really known. I don't know how much tuna you fed him; I think its a great food, if fed just occasionally. Its very oily fish, but I really haven't seen anything to suggest that it would be harmful.

 

[ogre]

I would tend to agree with you about keeping lower salinity but have read alot that makes me wonder what difference a higher salinity would make. Still can't see how that could be the cause of this death. I only feed every other day and the Eel never was one to over eat. I was always fishing food out that he didn't want. Always hungry but never a pig like the Lion.

 

[ccampbell57]

Lower salinity increases the oxygen and for lack of a better word makes the fish "less thirsty". I agree with the above that you may have been feeding the eel too much "junk" food in the long term. Basically, you can eat McDonalds and live on it for a long time but too much of one thing is not good. Variety of food is critical for SWF.
The issue is that you will never truly know what your eel died of. A lot of fish just up and die more often than not. My favorite porcupine puffer did the same thing after being in my system for 2.5 years. He litterally stopped eating, hid in his cave and died in my hands the next day.
Dont overthink it. Sorry for your loss.

 

[sepulatian]

Lowered salinity is alright for a few months, after that it becomes stressful. Kidney failure is a big problem with prolonged lowered salinity. The fish are not used to that low of SG. Their body functions properly in a SG of about 1.025.

 

[srfisher17]

Originally Posted by sepulatian
http:///forum/post/2784153
Lowered salinity is alright for a few months, after that it becomes stressful. Kidney failure is a big problem with prolonged lowered salinity. The fish are not used to that low of SG. Their body functions properly in a SG of about 1.025.
Do you have a source for this? I'm not 2nd guessing, I'd just like to get up to date on this subject. I admit that I've been flying by the seat of my pants in this hobby for many years. This forum has taught me plenty; and proven me wrong more than once. I did a quick bookshelf check and both Bob Fenner & Mike Paletta say most fish do just fine at 1.020. Fenner also mentions the big commercial outfits going as low as 1.017, but doesn't elaborate on long term effects of SG this low.
I don't often use my own experience as "proof"; but I kept a lot of fish at 1.017-1.018 for many years without incident. I had at least 10 fish that were 8-10 years old lost to Katrina and spent all their captivity at that low SG. (Not easy fish either) They were as healthy & active active as any tanks I've kept. If I didn't get into reefs, and the additional work involved with 2 batches of change water; I'd still be keeping fish in my dead coral tanks at that low level.
Just food for thought: wouldn't the physical effect on fish that were moved to a sg of about 1.017 be similar to the effects on fish captured at greater than normal depths (like many anthias, bandit angels, etc) and kept basically at sea level? It seems to me that the pressure of the deeper water would mimic increased SG. Maybe being too simplistic; but, hey, old guys need to learn too.

 

[hammerhed7]

the only downside I could see to a lower sg for fish would be a less stable ph, but I think the upsides stated above outweigh them. I have a reef that I keep at 1.025, and a fish only that runs at about 1.020. All inhabitants in both tanks are equally active, and aggressive eaters. I really see not difference in the fish kept at the different levels. I prefer a lower sg in my fish only as it keeps the oxygen level up, which isnt a concern in my reef with 20X turnover

 

[unleashed]

Originally Posted by sepulatian
http:///forum/post/2784153
Lowered salinity is alright for a few months, after that it becomes stressful. Kidney failure is a big problem with prolonged lowered salinity. The fish are not used to that low of SG. Their body functions properly in a SG of about 1.025.
I also highly agree with this member.. eels are tough critters when it comes to water quality but prolonged exposures to lower salinity can be fatal..eels tend to fair well in 1.023 -1.027.. unlike most fish eels cannot be held in hyposalinity safely... LFS dont keep most of thier stock long enough to notice long term effects.. i also recommend raising your SG for the well being of your other tank members