Help! Fish Dying!

[reeeedfish]

Help! My friends tank had 2 fish die within 3 days. What's strange is that the water test returned healthy. Except for a VERY low Ph and Buffering.


Dead Fish: 1 male dwarf gourami, 1 platy. All died within 3 days. Platy had tumor like desiese and dwarf gourami was inactive in final week.

Fish Still Alive: 1 bronze cory, 1 clown pleco, and three tiger barbs.

Possible Reasons of Death: Just recently accidently put 4 pounds of slate in without washing it. Fish were inactive before this happended though. Mabye incompatibility or overcrowding?

Please help my friend with his dead fish problem.

Please Advise!

 

[glolite]

Size of tank?

Water stats?

Any other symptoms ie: flicking against rocks etc

White stringy poo

 

[reeeedfish]

It is a 15g and no flicking but clear stringy poo is a yes.

Nitrate: 20

Nitrite:0

Ammonia: .25

Ph: 6.5

Low Alkalinity: don't know exactly.

 

[glolite]

Your friend needs to do a 50% water change to get rid of the ammonia.
White stringy poo can be a sign of disease or internal parascites but is this a newly set up tank?

 

[reeeedfish]

No it's a 2 year old tank and my friend did a water change three days ago.

 

[glolite]

No it's a 2 year old tank and my friend did a water change three days ago.

Doesn't matter when the water change was done, if there's ammonia in the water your friend needs to do another one.