Thank you for the excellent explanation of the two, I understand it much better. The GH turned a pale green upon the first drop, but the KHdidn't turn a dark yellow (I couldn't get it any darker) for about 18 drops.
You're welcome. My GH is the same, so you have very soft water. My "official" level according to the water authority is 7 ppm, which is less than one dGH, so the first drop changes to green. No issues, but stay with soft water fish, no moderately hard water species. I wouldn't worry about the KH here.
All the well water values are at zero, which is why I was kind of perplexed. I did seed with both ten gallon's filter media in the filter + "rinsing" the 5 gallon's filter media in the 29's water. I also planted a few days ago, and I'm hoping it'll fill in nicely!
The tank is holding at
>.1 ppm ammonia (maybe a tinge of green)
.1 ppm nitrite (just a tinge darker than the well water baseline)
40 nitrate
My previous suggestion still holds; do major water changes (ammonia and nitrite must be zero, and nitrate should come down before fish go in) and once the plants are growing, you're OK for a few fish. We can discuss which are better first--this has nothing to do with cycling issues but more with the biological system that takes a few months to become established, and some fish are less sensitive to this than others.
Rinsing filter media and using the water is not beneficial. The bacteria live on surfaces, called bio-films, that are sticky. Bacteria adhere to these quite well, and it is impossible to rinse them off, it would take a degree of scraping but I would not do this. There will by now be sufficient nitrifying bacteria in the tank, and they are not going to die off for a few weeks. Plus the plants use ammonia, and a lot of it, as their preferred source of nitrogen. Floating plants are ideal for this as they are so fast growing they work very well removing ammonia.
On the other hand, I noticed something bizarre while testing pH. I tested pH awhile back using high range pH, but I couldn't seem to find the bottle, so I did the normal pH test.
Well water - 7.6 (probably higher)
29 gallon - 7.1
5 gallon - Much darker than the highest range, probably at least an eight
Is there a correlation between plants or GH?
The GH, KH and pH are related, and the GH and KH primarily determines what the pH will do, with some exceptions. Here, I would expect the pH to lower once fish are present, producing waste which becomes organics that various bacteria breakdown, producing CO2. As well as the CO2 from respiration of fish, plants and some bacteria. This CO2 produces carbonic acid, and the pH lowers. This is fine with soft water fish. Even without fish, the lowering to 7.1 in the 29g is likely due to this process. Organics come from all over the place, and will be present in the water itself too.
The increase in the 5g is interesting...do you by any chance have calcareous substances in this tank? Rock, gravel or sand composed of calcareous minerals like calcium, limestone, dolomite, aragonite, coral, shells, marble...these will raise GH, KH and pH.
When testing the well water, shake it very briskly for a few minutes to out-gas the CO2; some may be present. This is not needed for the aquarium water.
Plants will affect GH and pH, but in my experience minimally; in very heavily planted aquaria the GH can lower due to plants. However, here the initial low GH is something you will have to deal with, by supplementing these minerals. A basic comprehensive supplement like Seachem's
Flourish Comprehensive or Brightwell Aquatics'
FlorinMulti work.
Byron.