you don't want to choose the volume... the pot, sustrate and whatever else was mixed in dictate water capacity. How much perlite or similar you use will impact this greatly. coco vs typical soil vs sphagnum peat moss etc..
So, with soil you'll want to find some balance of fertilize and water-only irrgation. This is something you'll ahve to work out over time.. take some notes on concentrations and ratios of nutes used (weighted average based on dosage of anything used can help make smarter adjustments and speed up the learning curve.) Your ratio of nutes will be slightly different due to how the soil was amended than any other garden. this is why you have to go through that learning curve on your own. One thing is certain.. it's much easier to add than it is to reduce something in the substrate/plant.
How often? again some personal preference here... every other irrigation? every third? This mostly depends on the concentration you use for your fertilizer... higher concentration means less frequent application... in your garden, the plant will use roughly the same amount of nutes per week or per month either way. Maybe, sligtly more if you do more frequent fertigations with lower concentration -- this is partly why soilless is a bit faster growth - not necessarily better.. there are pros to soil too. like pH pretty much takes care of itself and being more forgiving withe fertilizer choices.
The other tidbit about fertilizing in soil -- again, something you need to learn to balance on your own -- the early ramp up. You soil will come with fertilizer in it... hopefully at a good ratio and safe concentration. you may not need much early on, but will want to ramp up as what comes amended in soil is used up by plant. 25% - 50% - 100%? its' somethign that depends on the soil you buy. Observe and react to plant.. e.g. if you see the cotyledons start to pale, probably a good time to start ramping up your fertilization, slowly. That should be first sign you see, typically. It's okay if plant sheds cotyledons, too.. don't react too much to them alone.. jsut a good signal the plant is ready for 'something'
Okay, back to volume.. with the above understood... water (fertilizer or water-only) until the entire volume gets wet -- minimal run off will ensure it... you want minimal runoff.. if you can dial in volume where it's just soggy at bottom, that's fine too.. might as well not leech the soil of the nutes it came with or if doing every 3rd fertigation, not leeching out what you provided inbetween.
Feeling the weight of the pot, and watering at same light-feeling will result in a consistent volume necessary to do the above. It may not be a rounded 500mL or 1.5mL, but if close you can round up if you want for an easier number to work with when mixing nutes... then you don't have any excess lying around until the 'next' time... though if you keep it dark and not overly warm, re-using it in a few days is safe 99.9% of the time. Longer is going to need some sort of agitation to avoid stagnation.
There's a lot written here but just keep it simple... be sure to saturate entire pot, then wait for top 1" to dry, and repeat (same process for fertilized or unfertiized water). Any runoff send down drain or toss ouside on any plant not in a pot.
it can be a mindless task eventually. you'll play mad scientist for a few grows trying to find the right balance, and eventually it'll just be by rote. The SOP will not change...
i'm not specifically familiar with bio-grow et al products, but i'm pretty sure it's not hard to find soil diaries using those products... check out some Germ through 2-3 weeks to see how they ramp up. consider that soil products to vary to some extent, too.. .but will bee a good gist of what you need to do, nonetheless.