3 Deaths Last Night (all Old Fish) Seriously High Nitrate

FishForums.net Pet of the Month
🐶 POTM Poll is Open! 🦎 Click here to Vote! 🐰

doc matt

New Member
Joined
Jun 21, 2005
Messages
15
Reaction score
0
I've just noticed 3 big fish have died over night

Tank size: 8ft
pH: 6.6
ammonia: 1.0
nitrite: 5.0
nitrate: 160
kH:
gH:
tank temp: 78

Fish Symptoms (include full description including lesion, color, location, fish behavior): as normal but seem to be gasping for air despite aeration in the tank.

Volume and Frequency of water changes: 1/4 every month

Chemical Additives or Media in your tank: no addidives, 2 big external filters

Tank inhabitants: Chichlids

Recent additions to your tank (living or decoration): None
 
How long as the tank been established? If it has been established for quite some months then the filters clearly aren't able to cope with the bio-load (Due to ammonia and nitrite being present). Alternatively your tank may not yet have cycled.

Those water stats are extremely worrying. You're fish are currently being subjected to ammonia poisoning (with ammonia anything above 0ppm), nitrite poisoning (anything much above 0ppm) and Nitrate poisoning (Reading above 40-50ppm are not really acceptable)

I'd suggest you up the frequency of water changes to 20% every week at least. And as for rectifying your current problems. Personally I would to a 50% change right now...but then that could cause the fish to go into shock. However seeing as they are currently being poisoned it might be worth the risk.

Also what exactly are the dimensions of the tank? What fish exactly are in the tank and how many? Also how big are each of the fish?
 
How long as the tank been established? If it has been established for quite some months then the filters clearly aren't able to cope with the bio-load (Due to ammonia and nitrite being present). Alternatively your tank may not yet have cycled.

Those water stats are extremely worrying. You're fish are currently being subjected to ammonia poisoning (with ammonia anything above 0ppm), nitrite poisoning (anything much above 0ppm) and Nitrate poisoning (Reading above 40-50ppm are not really acceptable)

I'd suggest you up the frequency of water changes to 20% every week at least. And as for rectifying your current problems. Personally I would to a 50% change right now...but then that could cause the fish to go into shock. However seeing as they are currently being poisoned it might be worth the risk.

Also what exactly are the dimensions of the tank? What fish exactly are in the tank and how many? Also how big are each of the fish?

Hi the tank is 5ft (was typing quickly b4, stuck 8ft down :blush: by 2ft by 2ft) the tank has been established since 2002 with these 25% water changes once a month and the filters cleaned out once a month but not the same time as the water change.

The tank houses mostly Malawi Chichlids. I have never had to buy any fish as they breed like mad with the strong ones surviving. There must be about 60 fish only about an inch long. The 7 deaths this weekend have all be the old fish who were very big about 3.5 to 4" long about 7 years old.

Did a slow 50% change yesterday and they seem much better today although one small one still seems a bit dopey. I have 2 Fluval 404 external filters with the inlets connected to undergravel filter tubes with undergravel filter also a spare pump doing rock aeration in the corners. There are about 15 fry in the tank about 1/4 inch long swimming around doing fine atm

Cheers
 
Looking at your potential stocking - this could be what's triggered your problem - could you please detail exactly what you have in the tank and the sizes please?
 
They go through an under gravel filter? This could be what caused the problem. Can you not hook them up properly with their correct inlets? If not then I suggest you do an extremely thorough clean of your substrate as it may well be that the under gravel filter is getting a bit clogged so slowing the externals down. If this is the case it would cause ammonia and nitrite to be present because the water isn't being processed fast enough by the bacteria.
If you genuinely only have 60 or so 1" length fish then that shouldn't be a problem. Though bear in mind if they're breeding as rapidly as you say then they won't be able to grow much more than 2" before you'll need to move them on. To make room for new fry.
 

Most reactions

trending

Staff online

Members online

Back
Top