question about API hardness tests

k maybe im just reading too much but seeing so many units to measure hardness and so many scales of what hard or soft is i think im just getting confused

my water tested at ph 7.6 on the low range test and 7.4 on the high range test (seems my PH is right between the 2 kits) with a KH of 4 (4 drops = 4dh/72ppm right?) and my GH was 7 (7drops = 7dh and 125ppm)

so i know the results are accurate im just trying to figure out what to do with them, some places im seeing a GH of 6-8 listed as hard and others im seeing 4-8 as soft??

heres one scale from thekrib.com
0 - 4 dH, 0 - 70 ppm : very soft
4 - 8 dH, 70 - 140 ppm : soft
8 - 12 dH, 140 - 210 ppm : medium hard
12 - 18 dH, 210 - 320 ppm : fairly hard
18 - 30 dH, 320 - 530 ppm : hard
higher : liquid rock (Lake Malawi and Los Angeles, CA)

and heres another taken from http://www.aquahobby.com/articles/e_parameters.php

ppm degrees defined as
0 â€" 50 0 â€" 3 soft
50 - 100 3 â€" 6 moderate soft
100 - 200 6 â€" 12 s light hard
200 â€" 300 12 â€" 18 moderate hard
300 â€" 450 18 â€" 25 hard
450+ 25+ extreme hard

im keeping SA's so im sure im fine for water parameters but it just seems confusing, am i on the low end of what they like or the high end? (im keeping bolivian rams, keyholes, angels, rummynose, corys) most places list fish as soft or hard not really giving specific ranges of hardness.