I’ve acquired Amazonia as my substrate. I’ve read In a number of forums here that you can plant in this straight away if you have a mature filter. Does that apply to a new set up including new filter or is it best to plant after a few weeks when the tank will be partially cycled?
The filter nor the substrate actualy needs to pre cycle.. Regarding the substrate it is fertilized, initialy it will leach excess ferts and unwanted toxic elements into the water column to much to sustain lifestock. After a few weeks, doing water changes flushing out these toxins from the substrate and water and give the substrate the time to develop nitrifying bacteria population (Cycling) than it will stop leaching, the bacteria convert the toxins to nitrates.
90% of the plants you plant are emersed form from the nurseries, if you plant these submersed all of them will go through transition from emersed to submersed grow form. This process causes old leaves to die, melt away and new submersed leaves will grow. This dying and regrowing process takes a few weeks. And while this process is going on you are doing water changes anyway and the bacteria is gradualy populating. Before the plants are done completely shedding and regrowing you could consider the tank partialy cycled. Measure for ammonia and nitrite after this and does this stay 0 for long enough the tank could be considered cycled enough for lifestock.
Most marcophytes (plants) can take this cycling periode without problems, they actualy help cycling because they also partialy take up ammonia as nutrient and all plants have already a bacteria population living in and on their roots. So you actualy adding bacteria with the plants.
The filter also slowly populates bacteria in this same periode..
Doing a plantless cycle isn't bad nor good.. It's just a way of doing it..
But exception, if you plan to go for realy delicate planting as said in the thread you probably red, Utricularia graminifolia which is a carnivore and doesn't care much for substrate and is intolerant against ammonia spikes and excess ferts. This type of plant likely doesn't survive the initial cycling periode. The ammonia and excess ferts in the water column will burn it to death. Than you need to wait for this process to ease down before you plant this..
That's the story in a nutshell..