Giving it another go

It's fortunate that you like Phalaenopsis, as they're quite easy to grow in the average house. You can also purchase them easily at grocery stores, if you don't mind a hybrid with no listed ancestry. The grocery store hybrids can be very pretty, just be aware that any with blue in the flowers are dyed, not natural. The flowers will regrow without that blue color.
If you buy one at a grocery store, it'll probably need repotting, but that's easy enough. There are plenty of commercial mixes that work just fine for phals. You might take the opportunity to pot it in a clear pot, as that makes it easy to see the roots and check if they're healthy and whether they need watering. You can then place that clear pot in a prettier pot, as long as the clear pot is elevated so water can drain.
A general rule of thumb for phals is to water them the day before the media goes dry. That is, if the plant takes 6 days to dry out, water it every 5 days. You should water by pouring water through the pot until the media is thoroughly moistened, and let any remaining water drip out.
The first time you water, look at the roots. You'll see them go from silvery-green to bright green. Never water while the roots are still bright green, they have to go all the way back to silvery-green.

 

Another way to tell when the media will go dry is to check it daily for the first couple of weeks. A phalaenopsis will tolerate going dry a few times as long as you catch the dryness pretty quickly, so you can simply let it go dry a few times to learn how long it takes, then remember that time and water slightly beforehand.

A third way is to watch the bottom roots. When the roots at the bottom of the pot have gone completely back to their pre-watering color, it's probably about time to water.

You should be able to see the tops of some roots on the surface of the pot. For a starter orchid, I'd recommend a transparent plastic pot, as you can then look at the roots through the wall and see what state they're in. It's also nice to watch the roots grow.

Tap water is often fine for hybrid phals, provided you water them by pouring plenty of water through the pot to rinse out lingering minerals, though it depends on your area and water quality. Particularly if you've gotten a grocery store phal, as they're usually hybrids with at least some emphasis on hardiness.

For the media, look for something that has a mixture of bark chunks, charcoal or perlite, and sphagnum or peat. Many different medias will work for phals, up to and including pure long-fiber sphagnum (if you water very carefully so as not to smother it), but a basic commercial orchid mix will generally work fine. Soak the mix for a few hours before repotting, preferably, it generally comes very dry and then needs to be re-hydrated so it will absorb water at all.

 

Submerging the orchid in water for that long might be more than it needs. Make sure the pot drains very well, so that the only moisture left is in the media, not in droplets. Also, make sure you pick a media that doesn't stay soggy- sogginess kills orchids. Pick up some pieces of the media and squeeze them; if water drips out, it's too wet.

Checking whether the individual plants need watering is a good idea, particularly when giving that much water. Err on the side of too dry. A phal that gets too dry will shrivel, but can recover (unless left bone-dry for a long time), whereas a phal that stays too wet and starts rotting is often doomed.

You'll find many, many different opinions on how much and how often to fertilize. A very dilute fertilizer in every watering can be a good option, particularly when using RO water that doesn't have any minerals or anything in it. A slightly less dilute fertilizer once a week is also good. Most orchids are epiphytes, meaning they grow attached to trees, so most of them don't need much fertilizer at all. Watering and decent air movement is far more important, then light. Fertilizer is often the least important factor in growing orchids, particularly since they do get some nutrition from their potting media.

 

Paphs are a completely different orchid species, largely unrelated to phals. They're a semi-terrestrial plant; they grow in the leaf litter on the forest floor, and sometimes in pockets of leaf litter caught on cliffs or in trees. They're reasonably similar in care, due to being reasonably similar in shape and habit.

They like to stay a bit more moist, yes, but should never be soggy. No orchid (that I'm aware of) should ever be soggy. If you get a kitchen sponge, run it thoroughly under the tap, and then squeeze it until it stops dripping, that's a good example of how moist is good. You'll want to avoid them drying out fully, but they should get slightly less moist between waterings.

 

Sorry, let me rephrase.

With the Paphs, you'll want to water them, then let the media get slightly less moist than it was when it was first watered. If you imagine the level of wetness as a meter, like a gas gauge, you'll want the wetness level to go down. You don't want it to get to dry, you just want it to go down some, then you water again to bring it back up. With Phals, you let the imaginary wetness meter get closer to dry than you do with Paphs.

The media will get very wet when you first water, but you want that wetness to go down to something near wrung-out-sponge level pretty fast. That's what the drainage is for.

 

Reverse osmosis water works great for orchids if your tap water is especially bad. It might be good to mix a small amount of tap into the RO water, to add some minerals back. Some people do water their potted orchids exclusively with RO water, and that works fine as long as you remember to fertilize with something that adds calcium. RO water is, after all, very similar to rainwater. Though rainwater usually has pollen and dust in it.

Since we're not keeping fish, we don't need to worry much about pH, as long as it's not anything bizarre. PPM doesn't matter hugely for a lot of large potted orchids, but if you're really concerned, aim for 50 or below. That's the tolerance of many carnivorous plants, which are native to mineral-starved bogs and will die if given minerals, as they're unable to filter the minerals out. If water is good enough for them, it's definitely good enough for orchids.

I'm not currently growing any potted orchids, only mounted minis and micro-minis, and I water them with RO water. They're doing quite well on that, and on once-weekly gentle fertilizer. If I gave them tap water, they would probably shrivel up very shortly; a lot of these are cloud forest epiphytes, which naturally grow in bits of moss on twigs, and get very, very few minerals in their native habitat.

 

If the water is "hard" - lots of calcium - Paphs actually tend to like it! At the Huntington Botanic Garden in southern California, they found that their world-class Paph collection actually does better with well water that ranges from 200-800 ppm TDS (high in calcium carbonate) than with RO. Now, if your water is high in sodium, that's another story - then diluting with RO might be advisable. So it depends on what makes the water "bad"

 

Are you able to get a water quality report from your local water treatment plant? That sort of information is often available for free online or with a phone call. RO with CalMax should be good, but you'd save yourself some trouble if you could just go ahead and use tap.