Substrate

[StandbySetting]

In a low tech tank a nutrient rich substrate really isn't necessary, also the fertiliser you're dosing (plantmin) only contains Micro nutrients, you ideally want a fertiliser with Macro's as well as Micro's but you could probably get away without dosing anyway as your fish will be providing nutrients.

 

[dalethewhale]

haha ok, thanks for the advice
Yeah i know the fertiliser doesn't contain nitrates and phosphates etc but i figured my fish would provide them, i'm only dosing it at all because some of my amazon swords had very thin leaves and brown spots

 

[StandbySetting]

Brown spots are generally a K[sup]+[/sup] deficiency.