Hi MissClaire
I'm sorry to hear that your fish are giving you so much trouble.
Your pH problems, while not the direct cause of your losses, have probably contributed to them. Any changes to the water can contribute to stress that weaken the fishes immune systems and leave them open to contracting other diseases. Since you have had a number of different kinds of fish die with no clear cut disease, I would think the problem is bacterial in origin.
Everyone has harmful as well as beneficial bacteria in their tanks at all times, but it is only when the fish become weakened from one thing or another, that they can cause harm.
I see you've had problems with popeye, which can be bacterial in origin, and also mysterious deaths. Bacterial infections can strike and kill fish quickly, with no symptoms or slowly, with finrot, popeye, so called "mouth fungus," or other symptoms showing. If you see white patches on the fish it's possibly a sign of bacterial infection. It your fish look like they have been sprinkled with salt, (lots of tiny spots) it is ich. It's important that you know the difference because the treatment is very different.
With discus in your tank, one thing you can't do is lower the temperature to the point where it would slow the growth of harmful bacteria. You can, however, add additional aeration which will help, and treat with a strong medicine. I don't know what you have available to you in Australia, but if you can get antibiotics, ask the person at the lfs to recommend one. I would pass by the easy answers like MelaFix in this case, since you have already been losing fish.
Above all, keep your water clean with frequent and large water changes, and stabilize the pH. Also, be sure to feed your fish the best, most nutritious food available.
Good luck. I hope your fish get well soon, and will be looking forward to hearing some good news about them.
I'm sorry to hear that your fish are giving you so much trouble.
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Your pH problems, while not the direct cause of your losses, have probably contributed to them. Any changes to the water can contribute to stress that weaken the fishes immune systems and leave them open to contracting other diseases. Since you have had a number of different kinds of fish die with no clear cut disease, I would think the problem is bacterial in origin.
Everyone has harmful as well as beneficial bacteria in their tanks at all times, but it is only when the fish become weakened from one thing or another, that they can cause harm.
I see you've had problems with popeye, which can be bacterial in origin, and also mysterious deaths. Bacterial infections can strike and kill fish quickly, with no symptoms or slowly, with finrot, popeye, so called "mouth fungus," or other symptoms showing. If you see white patches on the fish it's possibly a sign of bacterial infection. It your fish look like they have been sprinkled with salt, (lots of tiny spots) it is ich. It's important that you know the difference because the treatment is very different.
With discus in your tank, one thing you can't do is lower the temperature to the point where it would slow the growth of harmful bacteria. You can, however, add additional aeration which will help, and treat with a strong medicine. I don't know what you have available to you in Australia, but if you can get antibiotics, ask the person at the lfs to recommend one. I would pass by the easy answers like MelaFix in this case, since you have already been losing fish.
Above all, keep your water clean with frequent and large water changes, and stabilize the pH. Also, be sure to feed your fish the best, most nutritious food available.
Good luck. I hope your fish get well soon, and will be looking forward to hearing some good news about them.