Ah, this brings back memories for me-- I don't know what the manufacturer for these all glass tanks are, but I have used many of these in the past. Almost all the LFs in Hawai'i carry this type. The manufacturer is almost certainly not ADA.
From my experience, 13 watts isn't enough to get "high" lighting for these tanks. Under 13 watts marsilea was very happy for me, but glosso would not stand a chance-- let alone HC. I had good experience with 19 watts with moss foreground. For some reason I didn't use creaping plants in that tank. Another time I used 30+ watts and got the glosso to be really happy-- unfotunately the moss died.
26 watts worked well for me all-around. The glosso didn't grow as fast, but everything else did quite well. I don't think HC will do well in anything under 20 watts-- which still probably isn't enough by itself.
Well, the lighting really depends. Amano's 1g from his book has 20+ watts of light. But I've also seen attractive tanks with only 7-9 watts, but those never involved creeping foreground plants other than marsilea.