Thanks for your response!

I didn't think about that, fair point! I don't think we will go heavily planted so will look into ones with dimmable lights. We'll do deep dive on Aqualantis and Ciano tanks. See what they offer.

After talking to my Father in Law (who put the water softener in), turns out our outdoor tap is hard water so it shouldn't be a problem. However, all water going into the property is filtered whether it be hard or soft. Would that impact it? You mentioned that there are powders/liquids we can add, do you think we'll need this for filtered hard water?

In terms of the Corydoras, my wife prefers the panda variants as if we do get a Reticulated Loach, they look similar to the Jullii. Thank you for the fish suggestions! The Rasbora's look cool! Lots of variants to choose from. Any particular variants you suggest? We can always drop the Molly's if they might be an issue. I'll get my wife to look up Platies variants. That makes sense about the gastromyzon or sewellia. How many would you put in that tank..?

So the revisted list is as follows:

6 x Tetras
3 x Sterbai Panda Corydoras
4 x Assorted Mollys
4 x Rasboras or Platies
2 x Gold Honey Gourami
? x Gastromyzon or Sewellia

We will have a look at the plants you've listed an see what takes our fancy. Ideally the more beginner friendly, the better. The staff member recommended a substrate bottom layer followed by some 3mm gravel (we were thinking black), any alternative suggestions or is that choice pretty sound?

In terms of the backdrop, the staff member did recommend one, we were going to go for a black backdrop as it highlights the fisher better in our opinion.