Join Date: Jun 2020
Location: Middle Tennessee
I think 10 is plenty old enough to do a planted tank, given that their interest initiates the set up! I'd ask them what aspects of fish keeping they're most interested in and go from there. As in, is their heart set on giant goldfish? Livebearers? Oscars? Florescent pink and yellow gravel with Spongebob decorations? In my opinion, smaller tanks are actually a little more tricky to start with than say, a 10 gallon, due to accessibility of the hardware, ease of maintenance, system stability, etc. I feel like we here on this forum have a lot of preconceived notions of what success looks like, but kids are blessed with not having fully formed their addiction to perfection yet. All of life is an experiment!
I have [an overstocked] community tank that I don't fertilize or dose with CO2, and it's full of plants. It would never be mistaken for a fine art Igwami style tank, but I enjoy the bustling, natural aesthetic. I would bet that a kid is going to be more into a wild aesthetic with a lot of fish activity than a formal scape anyway.
To the list of plant suggestions, I'd add dwarf lily bulbs. Watching the bulbs sprout and grow is very cool and rewarding. I recently added a bundle of Temple plant to my 5 gallon, and it seems to be a very undemanding and luscious plant thus far, though I don't see much talk about that plant here, so maybe there's a downside I'm ignorant to. I've had great luck with Eco-Complete in my low tech tanks. If I was was advising a new fishkeeper, honestly of any age, I'd suggest a 10 gallon tank with Eco-Complete and definitely trying some undemanding plants.
That's exciting and sweet that you get to usher in a new generation to this hobby. I hope they, and you, enjoy the process!