All my fish dead

[Keith Russell]

I woke this morning to all my fish dead. Again! I’m devastated. Yesterday I did a water change of 10 gallons and all was good. This is a 40 tall reef. Mixed. All the corals are grea. Open, colorful. Fully extended. I checked my chemistry this morning after finding the dead fish. Ph7 alk 2.5, 7.0, am. 0 nitrites 0 nitrates 50. Salinity 1.022. I realize the numbers are low , but every one was alive last night. Any ideas please

 

[Lbrdsoxfan]

The parameters aren't too out of whack. The key one I don't see is temp?

 

[davidcalgary29]

pH at 7 is very low, too.

The only thing I've experienced that can wipe out a tank in that span of time is a chemical contaminant and/or anoxic conditions. I'd point at the latter if corals and inverts are fine.

 

[ninjamyst]

How many fish, how old is tank, did you check for stray voltage, did power go out middle of the night?

 

[C_AWOL]

I don't think its possible for your ph to be just 7 and alk to be 2,5 in a marine situation.
Did you mean to type 8 and something a lot higher than 2.5 in alk?

 

[Keith Russell]

Water temp 78

 

[Keith Russell]

I don't think its possible for your ph to be just 7 and alk to be 2,5 in a marine situation.
Did you mean to type 8 and something a lot higher than 2.5 in alk?

On my Red Sea test card, I used 0.50 titrant. The Meq/L is 2.5 the dKH is 7.0

 

[TheReefDiary]

On my Red Sea test card, I used 0.50 titrant. The Meq/L is 2.5 the dKH is 7.0

Did you clean at all around the tank last night? Did you have something on your hands you didn't realize?

Figuring out these kind of events is essentially process of elimination and even then youre still kind of guessing as to what really happened.

 

[C_AWOL]

On my Red Sea test card, I used 0.50 titrant. The Meq/L is 2.5 the dKH is 7.0

Ah got it, you were listing it as meg/l and not as dkh. Was a bit confused since you stated pH was 7 and alk was 2.5 in the same sentence which would make people assume its an inaccurate reading or straight up freshwater of sorts.

Most likely its oxygen deprivation/some kind of contaminant since corals ime can survive outages a lot longer than fish can. Your listed temperature of 78F is fine as well.

 

[Keith Russell]

How many fish, how old is tank, did you check for stray voltage, did power go out middle of the night?

6 fish. I added a cabbage leather yesterday. The only thing out of the ordinary was my skimmer overflowed into the overflow bucket. About 3 this morning we heard the power heads making noise so I added fresh water that I got yesterday to top the tank off.

 

[Keith Russell]

How many fish, how old is tank, did you check for stray voltage, did power go out middle of the night?

The yak is 5 years old. I put my hands in and felt no jolt. The peppermint shrimp is good. The s ails and hermits are good

 

[Keith Russell]

The parameters aren't too out of whack. The key one I don't see is temp?

The temp is 78

 

[Tamberav]

Did you dip the coral or anything?

What test kit do you use to check pH?

 

[Keith Russell]

pH at 7 is very low, too.

The only thing I've experienced that can wipe out a tank in that span of time is a chemical contaminant and/or anoxic conditions. I'd point at the latter if corals and inverts are fine.

Would that low of ph kill all the fish?

 

[TheReefDiary]

Would that low of ph kill all the fish?

You definitely don't want a pH that low. Any lower than that and your in acidic territory.

 

[Lavey29]

If they all died overnight that indicates an 02 deprivation in the tank to me.

 

[Randy Holmes-Farley Verified Community Expert]

Ammonia and oxygen are likely possibilities as is something not supposed to get into the tank, but most things that kill fish also irritate corals.

How long had you had the fish?

 

[vetteguy53081]

I woke this morning to all my fish dead. Again! I’m devastated. Yesterday I did a water change of 10 gallons and all was good. This is a 40 tall reef. Mixed. All the corals are grea. Open, colorful. Fully extended. I checked my chemistry this morning after finding the dead fish. Ph7 alk 2.5, 7.0, am. 0 nitrites 0 nitrates 50. Salinity 1.022. I realize the numbers are low , but every one was alive last night. Any ideas please

As much as I hate to say, all your levels are below standards
What test kits are you using ?
With coral fine and fish not, I have certain concerns. Starting with temperature, was new water RODI or Tap water from faucet and was it same temp or tad warmer than tank temp and not cooler?
Saturated oxygen is my next concern and did heater by chance crack during water change ?
Typical parameters (ranges):
Temp 77-79
ph 8.1-8.3
salinity 1.024 - 1.025
nitrate < .10
phos < .04 - .06
Ammonia < .03
mG 1300-1350
Alk 8-11
CA 400- 440

 

[Vicboihere]

My protein skimmer is the key to adding O2 to the tank for my fish, if yours was not correctly working it could be the issue. Smaller reef tanks can have oxygen deprivation issues with too many or too large of fish.

 

[2Sunny]

pH of 7.0 will kill the fish especially if it was a result of excess top off resulting in a rapid change in salinity along with excess CO2