TDS for my tap water is 62ppm - for this tank it is 112ppm.
Do 30% water change, add 1 pump easy green then measure nitrate, phosphate and TDS. This gives you start of week baseline. What you want is to get a gauge on is how those creep up (or down) over the week, measure again before you do next pump of easy green. Did they go down or up? If N/P/TDS went up before you added next pump you can assume that increase is from (a) breakdown of food and waste in tank, (b) soil based substrate leaching ammonia into water column, (c) both of the above.
The idea is to change right amount of water and then dose at needed rate to keep a stable baseline throughout the week. It’s basically lather/rinse/repeat, water change is is rinse, dosing is lather. You zero in on a routine of water change, cleaning/maintenance/pruning and dosing for YOUR
tank. Once you get that routine worked out and purring along it really takes very little monitoring from you.
My little 7gal non co2 tank, 1 betta, 11 ember/neon tetra has rotala rotundifolia, red root floaters which grow like crazy. I change 1/2 gal week, thin out plants to keep them in line and then use 1gal milk jug of RO dosed with .375ml of Thrive to top off for evaporation and dose (daily) throughout the week. Only monitoring I do is use JBL test strip once week and maybe stick TDS pen in there once a month. If I notice TDS creeping up I’ll throw in a extra 1/2 gal water change.
The absurd plant growth/nutrient uptake and my thinning out of plants religiously are mainly what keeps my
tank maintained. By topping off for evaporation I’m feeding my plants/keeping levels up everyday. Feed my fish and add about 2 cups of the water everyday. If I miss a day I just double up on top off water next day, it’s such low level dosing it’s not a big deal.
Once you get that routine worked out your basically on autopilot unless you make a big change to fish population or plant mass/type of plants.