Lost 3 Fish After Water Change

[jamesmacc]

ost 3 fish this morning after last nights water change .. gutted 

 had the fish a week and they had settled well but two of them had been hanging out at the top of the tank above the spray bar out of the current and always looked a bit weak. they died and i also lost a tetra, thinking i might have stressed them out when adding more plants and doing the water change ?
 
i did the water change the same way i did my last tank and it was fine for 2 years .
i temperature matched the water in the sink before diverting it to the tank through a hose and adding seachem prime before the water when in and after it was in. the new tank water temp was perfect the tank never dropped above or below 25 degrees while doing it. i did re arrange a couple plants while i was changing the water so maybe i stressed them with my big wands waving about ?
 
its a 400 ltr tank
fx6 been cycled and running 2 months 
​40 % water change temp matched and prime dechlorinate added 
first water change since fish were added a week ago
 
am i doing something wrong or is it bad luck ? is 40% water change too much for a heavily planted tank 

 

[Ch4rlie]

i did the water change the same way i did my last tank and it was fine for 2 years .
i temperature matched the water in the sink before diverting it to the tank through a hose and adding seachem prime before the water when in and after it was in. the new tank water temp was perfect the tank never dropped above or below 25 degrees while doing it. i did re arrange a couple plants while i was changing the water so maybe i stressed them with my big wands waving about ?

 
Am a little confused by that sentence, to clarify, do you mean you added some prime before the water was being adding to your tank for refilling, and you added the rest of the prime after tank was refilled?
 
How much prime is being added btw?
 
 

its a 400 ltr tank
fx6 been cycled and running 2 months 
​40 % water change temp matched and prime dechlorinate added 
first water change since fish were added a week ago
 
am i doing something wrong or is it bad luck ? is 40% water change too much for a heavily planted tank 

 
I'd say 40% is perfectly fine, I actually change about 50% in my fish tanks, and they are all planted tanks btw.
 
Did you test the tank water at all once you found the loss of the 3 fish?
Might be worth testing the tap water as well just to be certain.

 

[jamesmacc]

 

i did the water change the same way i did my last tank and it was fine for 2 years .
i temperature matched the water in the sink before diverting it to the tank through a hose and adding seachem prime before the water when in and after it was in. the new tank water temp was perfect the tank never dropped above or below 25 degrees while doing it. i did re arrange a couple plants while i was changing the water so maybe i stressed them with my big wands waving about ?

 
Am a little confused by that sentence, to clarify, do you mean you added some prime before the water was being adding to your tank for refilling, and you added the rest of the prime after tank was refilled?
 
How much prime is being added btw?
 
 

its a 400 ltr tank
fx6 been cycled and running 2 months 
​40 % water change temp matched and prime dechlorinate added 
first water change since fish were added a week ago
 
am i doing something wrong or is it bad luck ? is 40% water change too much for a heavily planted tank 

 
I'd say 40% is perfectly fine, I actually change about 50% in my fish tanks, and they are all planted tanks btw.
 
Did you test the tank water at all once you found the loss of the 3 fish?
Might be worth testing the tap water as well just to be certain.
 

 
hello
so its says you need 1 cap full per 200l of new water added to the tank, but it says if adding prime direct to the tank you must base it on the tank volume which is just under 400 litres for me, so i add 1 cap full just as the hose starts to flow water into the tank and then i add the second cap right at the end when removing the hose, this means i have dosed 2 caps for 400l total volume of water as per the instructions . that's what i did for 2 years with my previous tank and never had a problem. i haven't been home yet but ill check the parameters when i get back tonight . i'm proper gutted and hoping i haven't caused them too much stress or done something wrong 

 

[StevenF]

 
so its says you need 1 cap full per 200l of new water added to the tank, but it says if adding prime direct to the tank you must base it on the tank volume which is just under 400 litres for me, so i add 1 cap full just as the hose starts to flow water into the tank and then i add the second cap right at the end when removing the hose, this means i have dosed 2 caps for 400l total volume of water as per the instructions .

 
Normally you  put the water in a bucket and add the conditioner, mix and wait a minute and then add the water to the tank.  That is that the first line says.  This is the least stressful way to do a water change.
 
However Sachem does recognize that the water bucket methods is not practical for large tanks.  For large tanks water continuously flows in by way of a hose.  For that case the bottle says to base the dose on the volume of the tank, not on the amount of water going in .  The reason for this difference is that Prime needs time to neutralize chlorine and ammonia in the tap water.  When water is coming in via a hose you don't have any time for the reaction to occur.  So a larger dose is added to accelerate the reaction rate. SeaChem does state that it is better to add it to the water first and then put it in the tank.
 
So you are dosing correctly per the instructions.  However adding 2ml to the entire tanks is more stressful to the fish.  and that might explain the fish loss.   So you are possibly doing high stress water changes on your tank.  Your fish loss may have been due to that or maybe something else.  Or possibly a combination of a high stress water change and other stresses the fish were experiencing.  
 
What i would do is to test your tap water before adding it to the aquarium for the presence of chlorine and ammonia.  If neither is present prime is probably not necessary.  And you could just add water to the tank without prime. OR you could use a lower dose of prime consistent with the amount of water being added.
 
I don't have a large tank just a small one.  What I did first was to test the water.  It always reads zero ammonia and chorine.   At first i used a conditioner but if I just needed to add a small amount of water to make up for evaporation, I didn't add the conditioner.  Nothing happened.  So the next time I added water i added more water again without conditioner.  And again nothing happened. 
 
I basically decreased the amount of conditioner I was using until I got confident I did''t need it.  I eventually worked my way down to zero water conditioner.  That only took a couple of months for my small tank.  I haven't used water conditioner for years.  I still have the bottle but it is about to expire and I will probably throw it away.
 
 
Another thing to keep in ming to keep in mind is some people,  including myself, put decorative sea shells or snail shells in the aquarium or used crushed coral.  These contain calcium carbonate and magnesium carbonate.  They cause the alkalinity of the water  to increase which stabilizes PH.  Do you know your alkalinity level?  If any chlorine does  get in the aquarium it will react (probably slowly) with the chlorine forming Calcium Chloride and magnesium chloride which are natural plant fertilizers.  Plants will eventually use this up keeping the tank safe.  Plants do need chlorine, calcium, and magnesium to live and will remove them from the water.  So if my water does have chlorine it is likely at very small levels and my alkalinity is high enough to neutralize it when it gets in the aquarium.

 

[ChadAT]

Doing a 40% water change a week after introducing new fish is not a good idea. When you introduce new fish to your aquarium the cycle is adjusted. Changing 40% would've thrown off your entire cycle. Re-arranging your aquarium is also stressful on the fish (generally not enough to kill them). I think you may have done too many things at once. Especially with young fish; keep in mind any fish you purchase from pet stores are generally very young.