Unwell Fish?

[j1k]

i have 4 silvertip tetras and 2 honey gouramies.
1 of my gouramies has been hiding for the last few days only really coming up for air.he has not taken any food now for the last 4 days. he doesnt seem to have lost any colour or show any signs of disease.I done readings yesterday PH7.4 ammonia 0.25 nitrite0 nitrate 5.0 i done 15% water change.any advice anyone...cheers
P.s last week i changed 30% of the gravel substrate for sand also 5 days ago i cleaned my filter and swapped 1 of the sponges for a new one

 

[Miss Wiggle]

the ammonia will be doing it, you need to do an immediate water change to get this down to 0, do as large a water change as you need to to achieve this, perhaps start with a 50% water change, then leave it an hr, re-test the water, if you still have any ammonia then do another one, keep going this way until it's down to 0.

You then need to look slightly more long term at why you have ammonia, I suspect it's to do with changing one of your filter sponges however I'd like some more background to make a full diagnosis.

Can you tell us how long the tank has been set up, what equipment you have running, what fish you have and how many of each species, what is your regular maintenance routine?

 

[j1k]

the ammonia will be doing it, you need to do an immediate water change to get this down to 0, do as large a water change as you need to to achieve this, perhaps start with a 50% water change, then leave it an hr, re-test the water, if you still have any ammonia then do another one, keep going this way until it's down to 0.

You then need to look slightly more long term at why you have ammonia, I suspect it's to do with changing one of your filter sponges however I'd like some more background to make a full diagnosis.

Can you tell us how long the tank has been set up, what equipment you have running, what fish you have and how many of each species, what is your regular maintenance routine?

i have 4 silvertip tetras 2 honey gouramies.tank has been going 7 weeks 3 without fish,i then added the tetras and 8 days later iadded the gouramies.it is a 60l tank with heater 6 plants an airstone and a stingray15 filter.i usually do 15% water change 3 times per week

 

[Miss Wiggle]

the tank is cycling then which is the problem, have a read of the link in my sig 'whats cycling' which explains it all and tells you what to do. then give us a shout if you have any questions about it.