im having 2 ft tank with plant and fishes inside..
using biofilter.. put outside the balcony.. the tank been doin well pass 3 month with few guppy inside.. i add fertilizer every week to reduce the nitrate level of the water.. and add water when water level drops.. change water within once every week.. i add ketapang leaf too to make acidic water so tht i'll get lesser algae attack and prevent parasite, fungus..

everything goes well until i add 10 guppy inside the tank..and others fishes like tetra and mouse fish.. thy looks ok.. like today i saw them swim freely, then the next day, i saw one fish die left with bone.. it jus die in a nite.. then th next few day.. it happen one by one.. i input 10, loss 10(one by one sometime 2).. !! until even i do water change(jus change the water.) it settle with few fishes surviving until now..

my question is wat make this happen? thy din show any sign of diseases.. and yet die in a nite.. water quality?

Those fish prefer water in the 7.0 range. I had a lot of guppies die from a sudden PH drop.

Sorry for ur loses..
IMO,
ur new arrival fish is died due to ph shock .Reason is that most of the aquarium fish live in the 7-7.6 water.since ur water is too acidic,the gill burn.

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We Keep CICHLIDS , We Don't Behave Like CICHLIDS !

Sorry for your lost...

yes, you have to adjust the pH to match the pH in the tank especially guppy. guppy is prones to pH shock. how about the remaining guppy??

oh ic.. omg.. no wonder the one i brought from last time is ok until now.. but the newly brought one.. 80% percent gone.. .
but so far.. for now.. its ok.. cos i din add any more fish..
but later will heh..

btwn how to avoid sudden ph rise? ketapang will surely lower the ph.. but it help me to prevent algea attack my tank.. any way to intro new fish to settled tank? normallly i jus mix the water tht got together wit fish while purchasing with settled tank..

normally what i am doing is put new comer with the water in the bag into a pail/hospital tank first and slowly add in 1/3 of settled water into the pail/hospital tank. then 1 or 2 hrs later add in another 1/3 of settled water into it... repeating 3 to 4 time till the pH for the pail/hospital tank is almost same as settled water's pH. lastly, add the new comer into the settled tank will do...

hope this help...