Unknown problem looming in my tank?

[CaptainMako]

Hey everybody, please try to offer help if you can.

I have a 29 gallon, cycled freshwater tank that has been established for over a year. It currently has five dalmatian mollies and a single dwarf gourami. I lost one molly a few days ago, it was growing continually skinnier and I think a prior issue with mouth fungus caused permanent damage, as it wouldn't eat. Winter has not effected my tank temperature, but now my gourami is being picky about eating and spends most of his time in the corner of the tank next to the heater. The rest of my mollies are just fine. They are being fed tetramin flakes and the occasional block of frozen brine shrimp.

I had a filter die a few weeks ago and I promptly replaced it, but just swamped the cycle filter pad into it. there was a short issue with my levels around then, but everything is fine now. A while before that though, I've had a massive influx of algae begin building up in all areas of the tank, I'm planning to take care of it when my water changer gets here in a few days.

As I type this, I just fed my fish and checked the gourami. I don't know when this happened, but his two "whiskers" that hang off the bottom of his torso have been torn off. I don't know when this happened, my mollies have never attacked anything but each other. I put a dose of melafix in the tank.

Please help. This is my first tank, and these fish have survived so many of my mistakes. Marine biology is my world, I would be heartbroken if I lost these fish.

Thank you so much,
-Shaun

 

[Mumma.of.two]

First two things need doing. Can you check your water parameters? What's are your ammonia, nitrite, nitrate and pH?
Do a large PWC to remove the melafix. It it's not recommended for labyrinth breathers (gourami, betta, paradise fish) because it can damage the organ.

 

[CaptainMako]

Sorry I wasn't able to get back.

I did a fairly large water change, and by the time I fed the fish and turned off their light for the night, the gourami seemed okay.
I turned my tank on this morning and the gourami was dead.

I don't know what's wrong. I put a dose of kordon ammonia detoxifier in there because my PWC's seem to do ****all.

 

[Mumma.of.two]

Sorry I wasn't able to get back.

I did a fairly large water change, and by the time I fed the fish and turned off their light for the night, the gourami seemed okay.
I turned my tank on this morning and the gourami was dead.

I don't know what's wrong. I put a dose of kordon ammonia detoxifier in there because my PWC's seem to do ****all.

Oh dear. I'm sorry to hear that. Ammonia detoxifiers are nasty. If you have ammonia or nitrite your tank isn't cycled.
What are the exact test result numbers? And what are you using to test?
The only things a tank needs are fresh water and dechlorinator.
Here is some info on cycling.
http://www.aquariumadvice.com/artic...g-but-I-already-have-fish-What-now/Page2.html

 

[CaptainMako]

My tank is cycled, it has been for a long time. Before weekly water changes were all I needed but I've been needing to do them more often. My ammonia and nitrites are fine, it's just my nitrates that have been going up quicker.

 

[Mumma.of.two]

My tank is cycled, it has been for a long time. Before weekly water changes were all I needed but I've been needing to do them more often. My ammonia and nitrites are fine, it's just my nitrates that have been going up quicker.

How big are your weekly PWC? They shouldn't be going up so fast you can't stay on top of them. You don't have an over stocked tank. Try keeping them under 20ppm by doing larger water changes. Are any of your other dish showing any signs of disease or stress? Have you checked your tap water for nitrates?