Help All My Fish Are Unhappy, And Tetras Have Died

[Whyteknight]

Hi,

I really hope you guys can help my fish!

I have a 120l aqua one tank that has been running for 3 months, it has / had 12 neon tetras, 5 rummy nose tetras, 5 guppies, 1 horse face loach, 1 male dwarf gourami 2 female gouramis, 1 pleco, and 2 coridoras, 1 dwarf rainbow fish, 2 baby clown loaches.

Substrate is 30% gravel 70% silver sand, i have lots of live pants all are healthy.

i do a 20% water change twice a month, the nitrate levels are

NO3 = 4
NO2 = 0
GH = 10d
KH= 6d
pH= 7

everything has been fine for months and all of a sudden the tetras started to look distressed and started gaspng at the surface, i did a 20% water change at 1 am and lowered the temp to 25 deg C (from 26) i dropped the water level by 2 inches so the filter outlet has started making lots of bubbles and lifted the sprinkler bar up from the filter media making more bubbles and surface disruption. this morning all the tetras are dead! all of the fish are gasping (even the horse face and plec are swimming up to the surface). i checked the gils of the dead rummy nose and they were fine and healthy pink.

I cleaned 1 of the 2 filter pannels a few days ago but left the ceramic beads in the water and the other filter pad. and the nitrate levels etc are still good so i dont think my tank is cycling.

Please help i really dont want to loose any more fish!

 

[Underwurlde]

You've missed out the most important one mate!

What are the levels of Ammonia (NH3/NH4)?
Also, can I ask you what filters did you clean and exactly HOW did you clean them?

Finally, what will the total mature length of all your fish be (in inches)?
12x Neon Tetra = 18"
5x Rummy nosed tetra = 10"
5x Guppies = 5"
1x Horse faced loach = 8"
3x Dwarf Gourami = 6"
1x Pleco = 20"
2x Corydoras = 5" (approx)
1x Dwarf Rainbow fish = 2.5"
2z Clown Loach = 24"

Total = 100" of fish there mate at LEAST 100 US Gallons or 380Litres. In other words your tank NEEDS TO BE AT LEAST THREE TIMES BIGGER. You really need to address this fact! No wonder your fish are dying they are suffocating in there! Also I have not touched on minimum stocking (of the same species) and stocking combinations you've got in there!

Sorry about this bad news....

Andy

 

[DarkEntity]

You are rather overstocked to say the least, and as mentioned you need the Ammonia test. You should be doing water changes weekly or 2 weekly not monthly for a tank that overstocked and well just in general.

Im assuming that since it was all fine that you have used tap water to clean the filter thus causing the tank to cycle again as there isnt enough bacteria to breakdown the pollutants in the water. Id be inclined to either get some mature media from someone local to help

Also you really need o get rid of 50% of the fish to someone who has a tank cable of supporting all the fish.

 

[Whyteknight]

Sorry should have stated we are in the process of setting up another tank that will house the Loaches (Horseface and Clowns) and the Plec. All of the fish are really small at the moment, the loaches and the plec are no bigger then 2 inches. The new tank is a 4ft tank and will become a loach tank. Our local fish man didnt seem to think the stock would be a problem until they had grown.

We seem to have discovered the problem and the fish are looking much happier

Thanks for your help

Jen

 

[Underwurlde]

Cool.... (Phew!)

Can I ask, what was the problem down to?

Andy

 

[Whyteknight]

We live in a reasonably hard water area and had some Ocean Rock and it was increasing the hardness of the water even more, what with the low oxygen levels and the increase in water hardness it had really upset the Tetra, however we have added an air stone and removed the rocks and put in some bog wood and done another water change and everyone is looking a hell of a lot happier!

 

[Whyteknight]

Well now im stumpped i have added an air stone to the tank checked all of the nitrate etc.. levels and they are all good. the fish started to look better for a bit but now they have started to die again! even the gourami's and corries are looking really ill. The gills on the horse face loach (which is now dead) were a bit darker than normal i.e not a nice red/pink, more like a maroon colour. Are there any diseases that can kill so many fish in 1 day? If i put all the remaining fish (3 gouramis 2 clowns 1 3"plec and a guppy) litre tank with no filtration just the air stone would the nitrates etc be ok so that i could maybe fully drain the tank and clean everything including the filter and risk putting them back in and cycling the tank with those few fish?

I have been trying to help these fish all day now and i really really cant bear the thought of loosing all of them! so far today i have driven the 20 mile to the pet shop twice bought a full test kit a huge piece of bog wood, an air pump air stone, nitrate removing stuff and even some oxygen tablets to hope they might help.

 

[Underwurlde]

OK, what is the ammonia, pH and temperature of the tank now?

Andy, exactly what fish are now in the tank?

I still think they were possibly suffocating... perhaps.

Have you vacc'd the substrate recently?

Andy

 

[Whyteknight]

Ammonia levels are 0.6mg/l. well they were! I decided to bite the bullet and do a 100% water change, so the remaining fish are in a 20litre bucket with new fresh water the heater and the air stone. hopefully they will survive the night then i can change 50% of the buket water and keep them in that till i get back from work and the big tank will be back up to temperature and i can put them back into it.

As for the fish that are left they are, 2 corries (1 inch long), 2 clowns (2 1/2 inches long), (1 plec 3 inch long), 1 guppie, 1 male dwarf gourami (2.5") 2 females (1" each)

i vac'd the sand about once a week (more than the bloody house.lol) as the bloody plec poo's everywhere! so i guess i did a 10% water change each week as i took about 1 bucket out when hoovering.

 

[WILDER]

There gasping because of bad water quality like been said was overstocked.
I would rehome the clown loaches the tanks to small for them.

 

[Underwurlde]

How did it go, are they OK, did they survive the night?

BTW, for future reference, you can use the hot water tap to match the water temperature going back into your tank, you don't have to purely use cold water and wait all night for your heater to bring the whole tank back up to temp (a little colder is OK).

How warm is the tank anyway? Lowering the temp will increase oxygenation levels.

Do you stir up the sand every time you vac? How deep is the sand? (I'm thinking anaerobic pockets here, a slim possibility).

Ammonia levels are 0.6mg/l.

Creeping up then? Keep a close eye on this - water change it down. Also need temp & pH levels with Ammonia levels so that the actual toxic ammonia levels can be calculated not just the Ammonia / Ammonium levels (that your test kit measures - Ammonium is safe, Ammonia highly toxic).

People are right in this advice: Pleco definately needs rehoming as do the loaches! I know it's all a bit hindsighty....

Andy

 

[Whyteknight]

well unfortunately i came home to a bucket of dead fish, with only the corry's and the pleco alive, so i guess i dont have to worry about re-homing the clowns!

I measured the water in the tank after a 99% change (i kept the filter full of water) and ammonia is 0 which to be honest is what the level was last night as well i think that the bog wood i added had just tinted the water a bit. all other readings are 0 so i guess im going to have to start from scratch.

Im still a bit worried about the cory's as they look quite weak and a bit thin now, i hope they can find the wafer i put in and build themselves up a bit. otherwise i think i may end up with just a plec.

As for the cause of this terrible event im stumpped as the water in our tank has been perfect for 3 months now.

This disease 'Costia' sounds like it produces the same sort of symptoms, so maybe cleaning the filter has caused a toxic spike that has stressed the fish and this disease has taken hold before the filter recoverd, and so the damage to the fish was already beyond repair?.

 

[MHunt]

Sorry, after reading the thread so far, it looks simply like a tank crash due to massive overstocking. After three months you should have only had about 40" worth of fish in you tank. An overstocked tank may run ok for a while, but as soon as something goes wrong, it goes wrong very quickly. Even if it was a disease, the overstocking made the problem ten times worse as the water quality was so poor for the fish.

As a guide, you should slowly stock to 1" per gallon for the first six months, then you could increase it to 2" per gallon after that as the tank itself will have matured. I'm sorry you had to learn this the hard way. I did, and my tank is healthier for it.

From now, i would try and maintain good water quality for the remaining fish, their presence should cycle the filter. Although you may get advice to return all the remaining fish, and do a fishless cycle. Wait till you have had the ammonia spike, and nitrite spike before attempting to add any more fish. Then stock slowly, give your good bacteria chance to cope with the added fish before adding more. Perhaps add one species a week starting with the one's you want to keep most of, your tetra schoal for example.

Good luck and sorry you've had to go through this. Many fishkeepers do at one time or another.

 

[Underwurlde]

I'm very sorry to hear that!

An unfortunate way to 'learn'...

As for the cause of this terrible event im stumpped as the water in our tank has been perfect for 3 months now.

Sorry, after reading the thread so far, it looks simply like a tank crash due to massive overstocking. After three months you should have only had about 40" worth of fish in you tank. An overstocked tank may run ok for a while, but as soon as something goes wrong, it goes wrong very quickly. Even if it was a disease, the overstocking made the problem ten times worse as the water quality was so poor for the fish.

Everyone here I think has been saying the same thing & has been reiterated again by MHunt.

As a guide, you should slowly stock to 1" per gallon for the first six months, then you could increase it to 2" per gallon after that as the tank itself will have matured

Not sure about the 2" bit MHunt. For mr the general rule if 1" / US gallon, regardless of maturity.

This disease 'Costia' sounds like it produces the same sort of symptoms

I doubt that. MAY be if you have RECENTLY added more fish (those being the diseased carriers and the ones that died first perhaps?).
If you really do think this is the case then QUARANTINE NEW FISH!

so maybe cleaning the filter has caused a toxic spike

Clean filters in old tank water. IF you cleaned your filter in tap water (without dechlorinating it first) then goodbye filter bacteria (did you do that?).

Let's hope your remaining fish are OK then: keep a VERY close eye on the stats (esp ammonia) and their behaviour.

Andy

 

[Whyteknight]

ok well its 6 hours since i put the 3 fish in the big tank again, and they still dont look great. the corry's are still lying a bit limp, and well plecs are not the most active of fish so im not sure about him.

Why are they still looking so bad even though the water is pretty much perfect again? i thought that once the fish were back in good water they would quickly perk up?