Can't Keep fish in new tank alive for 2 weeks-water was tested fine-over two months!

Thanks everybody.

My tank is a 10 gallon. I've read all about cycling a tank, but I guess it's time to get really scientific and chart it all out and do the right tests myself.

Regarding the heater, the new one will be more sensitive. I unplugged the other heater (no fish in there now) and the temperature did drop to 76 degrees, even though I had the gauge set at its lowest.

I WILL get the Freshwater Master test kit and ammonia and do the tests.

Question:
Should I start all over with the tank? Do a fishless cycle: Rinse all media, remove the Mopani wood, add new dechlorinated water, or just continue with what I got: do the ammonia test with the liquid tests? I'm just feeling cursed or that there's a contaminant in there.

I'd continue with what you have until you're sure the tank is fully cycled. We'll look at other grimlins if you're still losing fish after the tank is cycled.

Mark
 
Okay, I'll hold of on taking anything out of the tank. I ordered the Freshwater test kit and the new heater should be hear this week. Come to think of it, I did rinse out the filter sponge with hot tap water and then replaced the carbon at the same time after the Silver Molly had her babies and they died. Maybe that killed her -the levels may have changed. However as I mentioned the water tested fine at the pet store, and this guy seemed pretty good.

With all that said, I'll wait out until I get the test kit and measure and test everything.
 
Tap water has chlorine/chloramine and a rinse of the filter media with it could potentially kill of any of the nitrifying bacteria. Coupled with a complete change of media (the carbon) and that certainly could have caused a spike in params.

Generally it is recommended to wash any filter media in tank water or in any form of dechlorinated water.
 
For safety's sake remove as much water as possible. Add fresh, dechlorinated water and let the tank run a day to let the temp equalize then add 2 or 3 Zebra Danios. Feed them lightly once daily (if food ever touches the bottom during the cycle period you put too much in). Start testing for pH, ammonia and nitrite. When nitrite rises and then drops tank is cycled. If this doesn't work there's always coin collecting.
 
Is there a fish club nearby?

They can probably get you started with some filter media(introduces bacteria) and some healthy fish.

Getting the first tank started is the hardest. After that the issue is usually having enough places to keep your fish :)
 
Okay I got the Master test kit today and did tests on the water: ammonia, nitrate and nitrite tested zero. The PH is high though at 8.2.

I'll start the test to see if it's cycled: "adding ammonia, daily if needed, to keep it in the 2-3ppm range. Usually within a couple weeks you'll see the cycle progressing with a fall in ammonia and concomitant rise in nitrite. Within days this is typically followed by a fall in nitrite and a rise in nitrate.

When you can add ammonia up to 2 ppm and ammonia and nitrite test zero after 24 hrs your tank is cycled."
 
If that is the case, should I replace all water and rinse all the mopani wood and fake plants and gravel with tap. Then start from the beginning with conditioned water. I'm just want to eliminate the potenial bad ju-ju or disease in there.

Well after I say that, I think I do just want to start all over: more for peace of mind than anything else. Unless there are objects? I'll do the ammonia test first.
 
Okay I started the cycle.

I thoroughly cleaned everything first: bleached the gravel and tank, boiled the wood and a large rock. Rinsed everything like crazy many times. Put treated tap water in and have new filter media in there too.

Once my tank (10 gallon) is cycled can I add 3 1.5" fish or should I start with just one?
What would be a good fish to start with here. Keep in mind I've already killed 3 neon tetras, 1 Black Molly, 1 Silver Molly, and 1 Delta finned Betta.

I do like the Red Wag Platy but a pet store employee said to stay away from live bearers as they often have diseases or get diseases easily.
 
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