cleaning problem....fish dying

[izzycomosy]

Hi, can anyone please help every week I test the perameters and they are all within the limits I have 2 tanks, in the one I have a lot of small fish and the other is angel fish and parrot fish...now the problem is only with the 5ft tank,every week I clean the tanks and do a 20% water change add the water conditioner and so on but every week the day after the change I always get up in the morning and find 1 fish dead...only the day after the change and clean????,I have a fluval 404 and a jewel pump in the large tank
and a 305 fluval and jewel pump in the 4 ft I have not had any fish die in the 4ft tank and I do the same to the both tanks...any ideas...
I have checked the fish and there seems to be no signs of disease or change to their body..but they are still dead....what can you suggest please,cause at this rqate I wont have any fish left???

 

[TCTFish]

Try cutting back on the percentage of water changed in the tank you're experiencing problems to see if that helps. May also help to use Stress Coat and a bio additive for the change water. BTW...which fish are in which tank?

 

[izzycomosy]

parrot fish and angels are in the 4ft tank,and all the small ones in the 5ft tank ie: neons, tetres ,mollies, plecos ,and clown fish, kissing fish, red tailed shark fish, all together . I always use stress coat when I change the water and only do 20% water changeI have been using water stability but have not used that for about 3 weeks

 

[TCTFish]

Changing 20% of the water weekly can be too much for some of the fish to handle. Cut it back to about 10% once a week and start using the stability or some other bio additive again. Feed what the fish can eat in a two to three minute time period per day. Best to split that into two or more portions. So if you feed twice a day, that's one to one and a half minutes worth of food per feed. Skip a day or two out of the week and let the fish pick around the tank for leftovers. This will help keep nitrates down to help prevent the need of large water changes.

It is always best to do small, but frequent water changes than large water changes. Less stressing to the fish. Good to also test the pH of the change water prior to putting it in the tank. Sometimes change water can change the pH balance of the tank and can cause pH shock. I always prepared the change water prior to it going in the tank...pH, conditioners, and bio additives.

HTH. Please keep us informed of any progress.

 

[izzycomosy]

Many thanks for the advise,I shall do the smaller change in future,as you have advised
Regards
Izzycomosy