Are you going to handwater or use pump/timer/reservoirs? I start with handwatering and I collect the runoff to check volume and EC/ppm. General rule for coco is 20% runoff by volume. So 1 litre in you want 200ml runoff. Make sure you have some sort of way to deal with the runoff water. Either a pot suspended over a basin or drain hoses.
With a 3 gallon pot you can probably get away with once a day for most of the grow and maybe twice a day towards the end. The plant will tell you if you measure your runoff. If you put in 1 litre and get 200ml runoff you're fine. If the runoff drops to say 85ml then increase your volume. Try 1.5L in and see if you get 150ml runoff. IF you water once a day, increase the volume, and the runoff stays low, then you probably need to move to twice a day. Does that make sense?
At some point the coco won't hold any more water so not matter how much you put in, it just runs out. Hence, at some point twice a day, or more, works best. If you water by hand twice a day isn't hard. Larger watering volumes in a 3gal pot should be do-able. If you run small pots then pump/timer multiple waterings per day works.
I run 1.5gal airpots and only ever water twice a day.
Nutrients every watering. Nutes + water = fertigation. A MoG-ism.
The Mother Earth coco is pretty good. It does come pre-buffered but I still like to rinse it. I load my pots and then run seedling strength, 300ppm-ish, nute blend through the coco until the runoff reads in the 300ppm range. Some of the buffering solution can be quite high. ME brand seems decent enough. But I also like to presoak my pots completely.
pH is critical for coco, 5.8-6.2 is your range. Have a good pH pen and and ppm pen
and calibrate them. Do it before your grow and I would check the pH pen at least once a month.
My pre-grow setup:
@One Puff - If you're thinking about giving coco a try: This is just a quick look at how I like to setup my airpots and coco coir. Since the airpot bases are full of holes the coco tends to drop through when you are loading the pot. I simply put a single layer of unbleached coffee filters down...
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