Iím down to 65ppm TDS
now. It went down by 5ppm despite little water changes. Not up as you would expect. A conductivity of less than 100uS (micro Siemens) means there are very few ions of any description in the water. 65ppm = 101uS.
Despite this plants are doing amazing. They just keep growing. Granted i did add some soil in gel capsules to the substrate but the duckweed that was virtually gone is now growing back steadily and whats more is that the roots are growing long in to the water column. This suggests to me that because they canít access the substrate there must be enough nutrients in the water.
Iíve lots more fish now so nitrogen and co2
should be well covered but I think the fact the duckweed is growing back means that the fish food is also doing itís job. The amano shrimp are more visible and the snails are grazing more. Systems like this are extremely efficient systems so thereís never enough for algae.