Must I Select a Water Chemistry Plan, then Choose Fish

[Kmagnify]

Hello All,

Love the forums and I'm a new member with a 35 gallon hexagon tank that is cycled with normal water chemistry readings in terms of ammonia, nitrite and nitrates. That said.....

I have tetras, danios and platys that seem to do well with my water chemistry but my mollies seem to be succumbing slowly - one by one - including a balloon molly. My dwarf gourami only lasted a month. I'm down to about 15 fish total (molly, danios, tetras and platys).

Could my water simply be too "soft" or too fresh for mollies to truly thrive as well as the other freshwater species?

I have a huge piece of driftwood in the tank and read, somewhere, that it really changes the water chemistry. The aquarium features a medium-sized, disk air stone and uses the National Geographic brand filter for 40 gallon tanks.

I consulted Aqadvisor.com and used its aquarium calculator to match filter with allowed number of fish given the weird hexagon design that limits things.

Being a molly "Grim Reaper" is no fun and I'm happy to match the fish to my style of water (tap water, dechlorinated, Prime used with water changes).

 

[Delapool]

Hi, welcome

Imo I try and roughly match the fish to my water (mainly above / below 7) but I've mostly found the fish adapt and the lfs will be using the same water. Having said that I think if you try a fish type a few times and they wither away, than I move on. I've had no luck with platy's but mollies are fine.

Driftwood will tend to lower ph. Most tanks will tend to a lower ph over time but usually water changes balance this out.