Someone Help Please

[gtigaz]

Right were do i start, its a funny one this, i got a phone call from the missus the other day to say alot of our fish were dying out of the blue, so i got home as soon as i could tested the water, there was a tad of nitrite in 0.1, nitrate was quiet high, ph 7.5, ammonia 0, so i had a look at the fish and they looked very lathargic and up a the top mostly (we have 2 excellent airstones) so im looking thinking id best do a big water change fast, so i did a 95% water change they then seemed to pickup abit after that so i turned everything back on and after a while the water seemed to go abit foggy and then the fish were back to being lathargic and up at the top and also sort of twitching abit, so i then cleaned the filter media in tank water (wasnt even that dirty) turned everything back on, no change. so i thought right il take the about 10 dead fish and a sample to the lfs see what they think, they were just asking have we got airstones, sometimes this happens etc, not much help really but there you go, so this morning, i got up to find another 2 fish dead, so i did a 50% change and have left everything off apart from the pump and they seem to be picking up now apart from 1 black male molly which is at the back at the bottom and it looks like its gone crazy just sort of rocking :s bizarre! 
 
can anyone help or have any ideas as to whats going on in my tank please
 
thanks gaz

was thinking maybe it could be something to do with the heater or airstones now maybe?

 

[lrhodes]

what WAs your water temp?

 

[Ch4rlie]

Sorry if this is a silly question for you, but is your tank cycled?
 
And you say your nitrate was quite high, what is the reading specifically?
 
But having nitrite should not be there at all if your tank and filter is properly cycled.
 
Water going foggy sound a bit like a bacterial bloom perhaps, this commonly happens usually at start of tank cycling.....

 

[TwoTankAmin]

When nitrite goes off he charts it may test as close to 0. Your fish are suffering from one or, or both of the following: ammonia poisoning and.or nitrite poisoning.
 
The way nitrite works to harm fish is not the same as ammonia. the nitrite enters the bloodstream of the fish and attaches to a site normally used by other things and to transport oxygen. As a result the fish appear to be suffocating from a lack of O in the water even when there is more than enough.
 
The most effective way to handle nitrite in a tank cycling with fish or going through a spike is by adding chloride at 10 times the concentration of the nitrite. The chloride attaches to the site the nitrite would which prevents the nitrite from doing so. This leaves the nitrite available to the bacteria which will use it and multiply to where they are handling it 100%.
 
If ammonia gets too high only reducing it will help. Too much ammonia and/or too long an exposure can also harm fish. It can cause gill damage which may or may not be reversible over time. It depends on how high the ammonia went (and its the toxic NH3 component not the way way less toxic NH4 component that does the harm). So is is possible that some of the problem was caused by higher ammonia levels before they came down to 0 and/or the nitrite issues.
 
Since you have provided no series of historical readings and what was done in terms of water changes, no information on thank size, no information on how you cycled the tank etc., this is the best I can offer under the circumstances. I would need a bunch more info to be more certain or what went wrong.

 

[gtigaz]

ok thanks for the reply, everything seems to be getting back to normal now, the tank has been properly cycled its been up and runningfor 9 months now and never had any problems, i do 20% water changes once a week, the tank is 250 litres, ive been and got a new heaterso hopefully it will have been that as the water is always as it should be, the clown loach have never shown any signs of the water being out either and they are the fish to tell you if anything is wrong lol, the nitrate level was 40ppm

 

[gtigaz]

everything does seem to be back to normal, even the black Molly is trying his luck with the white Molly, strange, only thing ive changed is the heater the water isn't clouding up now or anything very weird

 

[Ch4rlie]

Well, lets hope its as simple as that. May have been a faulty or cracked heater!
 
Fingers crossed that solves your problems