Need Immediate Advice, Just Lost One Fish

[john3344]

brought home some new discus today to add to a 90 day old tank that is cycled and had many small community fish at one point. I got it down to 10 small fish and added 4 discus today. All seemed fine until about an hour ago. I came down to the tank to find one discus on the bottom. the other 3 discus gasping for air. I immediate changed about 10 gallons of water of the 55 gallon tank.

eheim canister and large sponge filter. Ammonia and pH tests less than an hour earlier were good.

the 3 remaining discuss immediate started to swim around (and were hiding some too)

I have had some on and off cloudiness in water the last week or so.

I changed about 25% water before adding discus. let them aclimate for about an hour, adding water to their bags.

The cloudiness was largely gone when I added the new fish, probably due to the water change, and the cloudiness was very slight to start.

After a few hours the cloudiness grew some, but tests were still fine. 0 ammonia, 0 nitrite pH about 6.8 (which is what they told me they had at the store)

I assume the bacteria bloom was sucking oxygen. How do I get them through the night?

I added in an air stone and cranked that up. That's in addition to the bubble sponge filter already in there.

All other fish appear to be fine. NO behavior similar to the Discus.

any assistance would be greatly appreciated.

 

[WILDER]

What test kit are you using? Can you post water stats please.
How many fish and which type.
What was the ph of the store to your tank.
How do the fish gills look.
Any signs of flicking and rubbing.
How are the other fish in the tank acting.

 

[Colin_T]

do you have a CO2 unit running on the tank? If so then turn it down.
There might have been some chlorine in the water from the water change. Do you dechlorinate the water before adding it to the tank?

Maximise surface turbulence to increase the oxygen levels in the water. Keep the feeding down for a few days to reduce the waste in the water and possible associated ammonia problems.

 

[john3344]

Update:

I did not take the time to do a test when things looked bad last night. I changed 10 gals of the 55 gallon tank.

The store tank had pH of 7 I was told.

Today my tank was about 7pH in the morning, it has dropped slightly. I have added some buffer. My tap water lately has not been well buffered.

Today the fish seem fine.

6 dwarf gouramis.
3 emerald cory cats.
3 Discus, two about 2.5" and one about 3.5-4"

The tank is still a little cloudy.

I added a bottle of Tetra SafeStart that the LFS guy gave me today.

I have had a long flexible "air bar" going since last might when things got bad

Ammonia, Nitrites and Nitrates have all been 0 today.
pH ~6.8
temp 82-83F
no CO2
some plants. canister filter rated for 80 gallons and a bubble sponge filter rated for 100gal


I was doing large water changes for the past week. I have a sense I did too many too soon and lost too much good bacteria. I was trying to get the tank pristine to add the Discus.

No flicking or rubbing, no odd fish behavior at all, all gills look ok

I'm not sure if I will keep the all these fish for long, I might convert this tank to discus only.
So far all the fish are generally calm with each other.

I dechlorinate the water

How many days might it take for the cloudiness to go away?

 

[WILDER]

Keep an eye on water stats.
Don't over feed.
How often do you maintain the tank.
When you preform a water change do you use a gravel vac.
it's rare to have a nitrate reading of 0. What is your tap nitrate reading and do you have live plants in the tank.

 

[Colin_T]

I was doing large water changes for the past week. I have a sense I did too many too soon and lost too much good bacteria. I was trying to get the tank pristine to add the Discus.

I'm not sure if I will keep the all these fish for long, I might convert this tank to discus only.
So far all the fish are generally calm with each other.

Water changes don't affect the filter bacteria. You can do a 100% water change with dechlorinated water and it won't affect the filter bacteria.
The beneficial filter bacteria live in the filter sponges and other media. Unless you wash the filter media in chlorinated tap water, you are unlikely to cause any water quality issues.

Discus actually do better when there are other types of fish in the tank. It helps stop them becoming nervous and skittish and keeps them more active and willing to come out in the open to feed.

 

[john3344]

Keep an eye on water stats.
Don't over feed.
How often do you maintain the tank.
When you preform a water change do you use a gravel vac.
it's rare to have a nitrate reading of 0. What is your tap nitrate reading and do you have live plants in the tank.

I did a water change to end the day, 25%
Ammonia was .25 before the water change
pH 6.4
everything else 0

During the past week I have been doing water changes some times every day, sometimes 10%, sometimes 60-70%
I had removed some plants that were creating a lot of mess on the gravel, so I was doing gravel vacs and water changes trying to get the tank pristine for the addition of the discus. I have been doing water changes at least once a week since I started the tank. Gravel vac at least once a week too.
In the past I was seeing nitrate.

Am I going through some sort of mini cycle?

The water is still slightly cloudy.

I removed one piece of driftwood and removed some carbon in the filter that also had some other stuff in it that is supposed to help remove ammonia. I was told it lowered the pH. I will need to test my driftwood to see if it's lowering the pH.

pH out of the tap is now 7.4

Nitrate out of the tap is 0.

I am using API drop tests

Is the tap water supposed to have nitrates?

I added some amazon sword plants yesterday. I already had some small plants and java fern and some moss balls.

The java fern has gotten yellowed in the last week. Even the Japanese moss balls don't look as dark green as they used to.

The fish have been nibbling at the floating fern ball.

(see pics)

one more photo

 

[WILDER]

Yes you can have a nitrate reading from tap water.
Don't add the ammonia stuff if it alter ph to much.

If your plants were causing alot of mess and rotting it can cause ammonia and nitrite readings.

 

[WhiteDevil]

I am a firm believer in PH doesnt matter, high and low at dangerous levels yes but I got fish rated for 7.0 in 8.4 water and growing each day, I tried to regulate at 7.0 and I had an issue of lathargic fish, let it be and it raised back up after a WC and everything is back to normal again.

 

[WILDER]

Only time ph is a concern if there a big swing.