Long-time lurker, first time poster.
So, I've done quite a bit of research on creating a peaceful community tank for my 20 gallon long, but have read conflicting information RE: how many sparkling gourami are suitable in a community tank (ex. some say a trio is best, some say a trio leaves an "odd man out", some say 4 to ensure pairing off, some say over 5 to have a large group). Given my current and future plans for stocking below, what's your opinion/experience?
Newly fishless cycled, added Dr. Tim's One and Only after initial fish stocking to ensure no spikes.
Moderately planted along edges and back wall, sand substrate, a small Aqueon Planted+ light, and a few cichlid rock caves (full tank shot attached). Recently ordered 12 2-3" Water Lettuce plants for floating cover to diffuse light. Also added 10+ small Catappa leaves (I use them for my betta - in his fancy Fluval Spec V - and had some left over).
Filtration: Aquaclear 50 w/ sponge filter (can be used up to 40 gal) over intake
Temp: 77 F
8 Harlequin Rasbora (I took all they had)
1 Sparkling Gourami (came in with a shipment of guppies to my LFS accidentally!)
My plan for future stocking
would be (taking Aqadvisor's stocking suggestions with a grain of salt):
11 Harlequin Rasbora (I've read they do best in odd numbers - right now I think I only have one male vs 7 females - and oh, he's enjoying it!)
3-5 Sparkling Gourami
6 Corydoras (leaning towards Pandas, but Pygmy's are adorable too and from what I've read, better for warmer water)
5 Amano shrimp (I've read about SG's penchant for eating small shrimp - willing to ex-nay these, but would like to try)
(per Aqadvisor, this is 83% stocked with 5 Sparkling Gouramis - w/o the shrimp, 80% exactly)
I'd originally planned to get two Honey Gourami, but the fish caretaker employee happened to mention the single Sparkling Gourami that came in with the guppies and I took advantage of the opportunity (you never see either of them around here).
Right now, Little Guy (the SG) is still quite small (pic attached) - I couldn't believe how young he looks! Could most likely still be considered a fry, but he's coloring up well, eating crushed flakes, and isn't as shy as I thought he'd be amongst the Harlequins (who've been "practice breeding" since the day I got them).
So, to get back to my original question: how many more sparkling gourami should I add to ensure everyone lives peacefully?
I understand they get aggressive when breeding, but am hoping the length of the tank provides enough space for up to 5 to get along. Btw, I'm perfectly happy adding only two more and even keeping the Harlequins at 8 instead of 11 - I'd much rather have happy fish than overcrowded fish!
Thanks for your thoughts!