Just getting back into planted tanks and looking around I just wanted some clarity on gh/kh.
Used to live in Surrey, and had much larger Co2 injected, low/mid light tanks, 50% EI dosed. Water was almost 100% glacier water and thus you can almost call it distilled water... super soft. Back then I just ran a large filter bag of aragonite in the canisters and dosed approx one table spoon of equilibrium into a 75-90 gal tank every 50% water change (Weekly). Worked well for many years... so well in fact that once I got into a routine, I never went back to check the levels and have since forgot how I came up with those amounts.. hahahaha...
So, I am now in the Township of Langley, we have a mix of well and glacier water. The water is harder here as I see the white calcium build up on all the pots, pans, etc... but test kits still show kh of 0.
20 Gallon tank, prob 15-18 gal of water it in it to account for substrate and decorations.
Low / medium Lighted tank, all easy plants (mostly swords, from chain swords, to amazon swords). Also some money wort and cabomba in the tank.
Gravel substrate, root tabs (jobe plant sticks + terra cotta clay balls)
satellite plus pro running 7.5 hours @ approx 70% output.
50% ei dosage
50% excel dose
Tank is approx 6 weeks old... just finished the cycle few days ago
Stock is a few tetra and a bunch of guppies
GH... don't know... I got ahead of myself and added some my plaster of paris into the tank before remember to test the GH..... it's cloudy right now as I wait for it to dissolve.
ammonia 0, nitrite 0 (finally.. YAY), Nitrate 5-10
As I'm keeping guppies this time, I was reading that I might need to up my gh and kh a bit... so.. pulled out my test kit and proceeded to check the kh. My last water change (40%) was 3 days ago and I blindly dosed 1/2 tsp of plaster of paris and 1/4 tsp of epson salt into the tank along with my macro and trace. I was surprised to see a KH of 0... big fat zero. Checked the tap water and also got a zero. At this point I was thinking that the test kit was faulty or the instructions where wrong, so I kept adding drops waiting for a colour change. 30 drops later, still all yellow.. (duh.. read the instructions).
I then proceeded to make myself some liquid rock. huge spoon of baking soda into a cup of tap water... yes the kit is working.. blue right away.
So few questions I have.
1) Where is all the KH? I added the gypson 3 days ago..... 1/2 tsp into a 20 gallon should be lots... is it not?
2) how much should I be adding to the tank to bring up the kh into a more suitable level...... I change 40% of the water every week (or that's the goal, it was every 2 days for the last few weeks as I tried to keep the levels under control during the cycle).
3) what kh/gh should I be aiming for to keep everything stable and happy?
Thanks in advance