I really appreciate the detailed replies. I think you're at the 'advanced' level, and I'm just at my 'first planted tank' level. Aqua- your input has been really helpful on all my posts getting through this startup !! I'm three weeks into this and a bit lost.
Please see specifics below, and I'll attach some pics. Input is appreciated.
Goal: Easy, low maintenance NPT, not frequent trimming needed. Jungle-ish with open space in the middle. Low tech, no ferts, no CO2.
This soil has never leached ammonia that I have measured. Levels have always been 0/0/0, e.g. at days 2, 6. 8 and 11. Even with a week no water changes when tank less than two weeks old, even with dirt seemingly everywhere from my messed up job filling it up, even with decaying plant matter around.
The plant existing growth dies off as I'd expect, but the new growth tries and then dies. Leaves whiten and/or turn black at the edges and die. The only plant not struggling, and actually doing OK, is jungle val. And so far the MTS are happy and multiplying.
I also have noticed what I think are detritus worms on the glass and swimming in the water during the 4h lights off period mid-afternoon.
Yesterday I pulled on a pennywort that I had stuck in the soil at tank startup to root, but had developed a whitening leaf, and the entire leaf and
stem dissolved in my hand. It was like rotted.
I poke the soil daily now, and bubbles are released throughout the tank, but I suspect they're CO2 rather than anaerobic conditions as no rotten egg smell.
I've also been adding pinches of finely ground fish food for nutrients/fertilizer/N/start cycle. I suspect that's brought me the MTS population explosion (Which I don't mind) and the detritus worms.
Specifics: Tank is three weeks old tomorrow. Added pure ammonia to 2-4ppm yesterday- thinking (a) a N source for the plants if that's the problem, and (b) cycling for stocking and (c) testing if maybe the 0/0/0 is because it IS cycled, and just needs more N.
Equip:20 gallon long with glass lid (& condensation); new Finnex stingray light (4h on, 4 h break, 4h on); Hydro III sponge filter (rated <40 gallons) run by Aquaclear powerhead 20 at lowest setting (hoping to have betta eventually) with oxygen input dialed to minimum (to minimize bubbles/keep CO2 int the tank); Aqueon Pro 100W heater
Substrate: MGOPM soil w sticks/clumps removed ~ 1" (I aimed for 1" depth; it is be more or less in some places as everything went wrong with the soil/cap/tank filling process), Black Diamond medium grade 20/40 sand ~ 1/2" depth (again, that was my goal, but it's more and less in some places)
Water: Hard, pH 8+
Livestock: Added nine Malaysian trumpet snails on day 2. No fish yet.
Plants: All newly purchased, so small. My plan is “try a variety of different stuff and see what lives, most probably won’t." I realize, for example, the Starogyne repens is a long shot.
Ludwigia repens; Nymphaes stellata (red lily); Jungle val; Echinodorus tenellus (small chain sword) x 3; Monoselenium tenerum (occ called pellia); Lysimachia nummularia aka Golden lloydiella (Gold Creeping Jenny); Staurogyne repens, Hydrocotyle leucocephala (pennywort)
Currently being shipped to me are: E. parviflorus tropica, Hygrophila corymbosa stricta, E. Indian Red Sword.
I tried java fern and the leaves just got black dots immediately (on the tops) and I gave it away.