Problem with fish please help?

rlculver09 · Nov 14, 2009

I have a 125 gallon tank with lots of coral and few fish,such as a yellow tang,sailfin tang,coral beauty,2 clowns,melonoma wrasp,scotter blenty,black blenny and a sand golby.1 arrow crab and 2 peppermint shrimp some snails and hermit crabs.Last night I noticed my sailfin he looked funny,and my yellow tang was swimming kinda sideways.I use rodi water and test it every week.when I got up this morning my coral beauty was dead,black beauty was dead,and my yellow tang also died.I'm sure the sailfin is also dead but I can't find him at this point.I have a protein skimmer and sump but have had it off for a couple of days. Also My corals look really happy.
I tested my water this moring and these were the readings:
Nitrate:Very yellow .25-.50
ph-7.8
salenity-1.021
Can anyone tell me whats going on and what I need to do to stop this from killing my other fish.I am going to do a water change about 30 gallons but what else can I do.?
Please Help

CoralBandit · Nov 14, 2009

Any swings?? temp, ph, salinity, usually this occurs from larger than normal water changes that are not accurately prepared (temp, ph and proper salinity adjustments). Temp can also obviously be caused by loss of power which would reduce [O2] as well. Need more info... you should bring your pH up in the 8's 8.1-8.4 and your salinity to 1.023-1.025 but these are not the immediate cause of your die off, more of a suggestion for future. Let me know more

Angels 2010 · Nov 14, 2009

what are you ammonia and nitrite levels?

Without your skimmer running, do you still have strong surface agitation? You'll need that in order to get O2 into your tank which will kill fish if too low or non-existent...

Fishcrazy06 · Nov 14, 2009

Angels 2010 said:
what are you ammonia and nitrite levels?

Without your skimmer running, do you still have strong surface agitation? You'll need that in order to get O2 into your tank which will kill fish if too low or non-existent...

I too would check these. I am thinking it would possibly be one of these 3.

Eric

Angels 2010 · Nov 14, 2009

just curious, but why no skimmer?

rlculver09 · Nov 14, 2009

I turned off my skimmer because I was having problems I need to go and buy another pump.
My Nitrate is .25-.50
PH 7.8.
I dont have any way to check my ammonia levels, the guy that services my tank checks it and it is always fine.I am taking him some water right now for him to check it,thanks for the info keep it coming This is the second time this has happen to me in the last year.
Thanks,
Robin

Angels 2010 · Nov 14, 2009

what was the cause the first time? And what about surface agitation? Very important with no skimmer. Do you have an air stone or air diffuser you can put in the tank? I have to think the oxygen level is too low.

If this is the second time, you might want to find a replacement for your tank maintenance guy...