Thank you!
I had to call the vet to the house to say goodbye to him today... devastated. Was going to be Monday, but his condition worstened overnight. Fortunately the vet was able to come to the house and he passed peacefully in the garden surrounded by loved ones. 15 years, but it's never enough time. I'm so sorry for your loss too, us dog lovers understand each other's pain! But we also know that the joy they bring for the time they're here outweighs this pain.
But I'm going to make a thread for that in the right place, not hijack yours any longer! Back to your own thread topic
I just try to be friendly and more helpful to beginners usually, then when I read back, sounded much flatter/colder to me than I aim for, although tone is so hard to send through text alone. I'm glad it didn't come across as harsh.
The water chemistry stuff is not in my skillset, and you've already got the guidance of the two very best people on the topic on the forum there,
@Byron and
@Essjay are rock solid, so you could not be in better hands!
So I'm just gonna address the stuff from pages one and two;
If
@emeraldking agrees that she seems to be a very dark gold dust molly, safe to say that she is
So her shape is potentially down to poor genetics/breeding, rather than sickness, which is both a pro and a con really! Safe to turn the heat back down and the lights back on though!
This is precisely why I don't think it's fair for you to blame yourself and say that it's all down to your own lack of knowledge! So many people are given truly terrible advice by fish stores, even employees/stores that should know better. It makes sense, as a beginner to the hobby, to trust the people who are selling the fish! They should know what they need and tell you what's most suitable to keep them successfully. I never blame someone who is new to the hobby for listening to them, because it makes perfect sense to! It's a sad fact that you're far from alone, way too many people find themselves in the same shoes when they first decide they'd like a tank, and all too often it winds up with a lot of dead fish, and a very sad owner who feels terrible, or leaves the hobby before they've had a chance to really get started.
I think the consensus in the hobby is never to trust fish store advice, and that the ones giving bad advice either genuinely don't know better (even though they should!) or they don't want to discourage sales by telling people they need to buy a bigger tank and wait weeks for cycling, and not to buy THIS sort of fish, etc etc. Lots of people would just walk out if told the truth, and go buy a tank and fish from their competitors instead. I'm just glad that you realised that the advice you were given was wrong, and exchanged your males for females, and bought a larger tank
And that you found your way here. Kudos to you for all that, it's clear you care about your fishes welfare and want the best for them, even when it's more complicated and expensive than the hobby initially seemed! Not everyone is willing to do all of this when they find out the store gave them bad info, so it really is good to see someone else join the hobby who cares as much as you do. Hope you stay and spend time here, and keep us updated on how Eva and the others are doing.
Temp range for mollies is 70-82°F (21-28°C), so I would gradually adjust the temperature back down to between 76-78, just adjust the heater and let it gradually go down again in its own time.
The best treatment for her now is plenty of fresh clean water, through water changes, 50% every day/every other day would be a great start at the moment. If you're following salt water treatment, which mollies are very tolerant of (any other fish in the tank? Or just the mollies?) then remember to re-add the amount of salt to the new water needed in order to replace the salt level from the water you've removed.
Wiping down the glass and using a gravel vac to clean the substrate is good, just don't 'overclean' the tank at the same time, okay? You can't really over do it when it comes to water changing, but it's important not to mess with the filter too much in a newer tank, and never to clean filter media straight under the tap - only to rinse the media in buckets of tank water you've pulled from the tank during water changes. So you don't risk harming the nitrifiying bacteria that keep your tank cycled
If her fins are damaged and it isn't just her colouring, the clean water and salt are the best treatment for both those, and any potential fungal infection from her head. Keep an eye out for bullying, fish can mercilessly target a weaker fish if it's sickly (makes sense, since in the wild, sick fish attract predators. Drive the sickly fish away is the instinct, but no where for the sickly fish to go in a tank!), a breeder net/box can make a good temporary separator if they reach that point. But in your photo, the tank looked quite open... more plants, especially floating and fast growing stem plants, help fish to feel safer, gives them space to avoid each other when needed, and also really helps with water quality
Phew, sorry for the extra long, essay reply! How is the white patch on her head looking now? Can always add more photos if you're unsure!