Today was a day for everything on the tank, it seemed. Well, the small one was simple. I rinsed its sponge filter last week, it doesn't seem to need it every week now- doesn't get as clogged. The java moss hasn't grown visibly and no dead leaves, so nothing to trim. It was just water replacement, ferts dose and clean the glass. The main tank needed more attention.
I am easing into dosing with the other macros- especially since the tanks already have nitrates from fishes- still not sure what's exactly needed and I get varying answers on the forums- but for now (since the tenner has fewer fish and thus lower nitrates, at 5ppm this week) I gave the ten gallon the normal recommended doses- 1/16 tsp KNO3, 1/32 tsp K2SO4 and half again that of KH2PO4. The twenty has at least 20ppm nitrate, so I gave it the regular dose of K2SO4 (1/16 tsp) and half-dose of KNO3 and KH2PO4 (1/16 and half the 1/32 respectively- to get half of 1/32 I used the same method as I did when putting small amounts of meds in the 5 gal QT- I dissolved 1/32 tsp into 10ml of tank water and dosed 5ml of that into the aquarium). Probably not exactly right but at least the plants are not dying anymore, most are growing better, and I will continue to tweak the doses and read up on stuff until I get it right.
(Now I'm being told on forums that if my plants show a need for extra ferts I really should give them CO2 as well- not what I had planned on! I might try it.... liquid version or DIY yeast supply, but that's another thing altogether...)