Fish Losses After Water Changes......

[Irf]

Hi all,

I occasionally lose a fish the day after I do a water change. Over the past three months I've lost four in this way, when I do weekly water changes. I'm changing around 25%. I use Tetra Aquasafe for the new water. I check the temp carefully.

Should I be leaving the tap water to stand for a while?

Can somebody help me?

Thanks....

 

[Tolak]

Check the pH of the tank, and the pH of the tap water.

I double up on the reccommended amount of dechlor, water companies will change the amount of chlorine, chloramine & buffers used due to varying circumstances.

 

[CFC]

Does the treatment state on the bottle that it neutralises heavy metals as well as chlorine and chloramine?
London tapwater is infamously full with traces of hundreds of different metals and toxins, all within safe limits for humans but potentially lethal for fish. I once sent off for a print out of what makes up our water and wished i hadnt, i now no longer drink unfiltered tapwater!!

 

[Irf]

I've checked the pH of the tank water against the tap water. Tank is 7.2 and tp is about 7.4. I also checked the tap water for nitrate. it was around 40ppm, which is high isn't it? My tank is around 10ppm.

I also looked at the dechlor stuff I use, Tetra Aquasafe. It says it locks up heavy metals and chlorine, but not chloramine. I read somewhere that chloramine is a mix of chlorine and ammonia - is that correct? This article then went on to say that removing the chlorine with a conventional product could result in trace amounts of liberated ammonia - enough to affect the fishes! Is this true/possible?

Thanks for any help..


Irf.

 

[CFC]

Thames water (Londons water supplier) do on occassion flush the system with chloramine so any conditioner you use must disable chloramine and chlorine to be 100% safe. The small ammount of ammonia released will be used up almost instantly by the bacteria in the filter in a mature tank but if the tank is still fairly new (under 6 months old) use something like Ammo Lock by API which de toxifies ammonia into its safer ammonium form.

40ppm nitrate is good for Thames water, a couple of years ago i was taking readings of 70ppm straight from the tap at this time of year, with higher usage the water gets recycled quicker and more nasties get left in.

 

[Irf]

Thanks CFC. Interestingly the Tetra Aquasafe that I use does not mention that it deals with chloramine. However Nutrafin Aquaplus does say that it wipes out chloramine. Maybe a switch of conditioner brands is called for?

Thanks for the Ammo Lock advice. I'll probably get some of that to use whenever I have to use the Tetra product.

Finally, there's news on my latest fish afflicted by my water change regime.... it has not died yet! It's a kuhli loach, and since yesterday it's been lying at the bottom the tank, on it's side, motionless and gasping. All the other fish are fine, and there is no external signs of damage/symptoms. Anyway I carefully transferred the poor thing to my breeder trap, so at least it's at the top of the tank if it's having trouble getting oxygen for any reason. It's definitely ill, cos it just let me pick it up - didn't even have the strength to make a run for it.

Irf.

 

[CFC]

If the tetra product doesnt disable chloramine then using ammo lock along side it will have no effect, you must use a conditioner that breaks the chlorine/ammonia chemical bond first before the ammo lock can de toxify the freed ammonia.

I would also recomend changing less water volume, if your tank nitrates are at 10ppm then a change of 25% is quite excessive and will be adding more nitrate to the water than was originally there, i would cut back to 10% per week. Thames water is quite high in KH so there is no worries of the calcium buffers being used and needing replenishing more often than that.

 

[Irf]

OK thanks CFC - that's really helpful.

I'll do what you suggest regarding water changes. What do you suggest regarding frequency? I've been trying to do a change in one week week intervals, but sometimes two weeks.

Maybe you are right - perhaps I've been overdoing it and stressing the poor guys out!!!!

Irf.

 

[CFC]

I'd say with your stocking 10% weekly would be fine, test the nitrates directly after a water change and then again before you do the next water change, if the nitrate has risen by more than 20ppm in that time increase the ammount of water changed by 5% and follow the same steps again until you reach the correct ammount.