Yea man there's not really anything fatal happing to your plant right now, just a bit excessive watering it seems to be. That will cause the style of droopiness and can call for some disfigured leaf development. As long as it is a healthy green, that leaf's still taking in energy from the light so no worries. Once you're back on a healthier feeding regime they should spike back up. Not always, either way they'll be fine.
Yes, the skinny leaves are just a different strain. Look into Indica, Sativa's and Ruderalis.
pH for soil should be 6.5-7.0 give or take .2 when watering to adjust and you'll still be safe. When watering make sure to pH at 6.8-7.0 to keep the pH stable in the soil. You might want to get the pH up a little more, that can also cause disfigured leaf growth. Tap water will be fine even if it is Hard water, with clones it may not be the best so check the ppm's. Don't do any flushing, specially every week, your roots need are too breath. You can flush when you switch from veg to flwr n for your last week, if you want, no other time is needed unless there is a problem. Otherwise, all you want is to get a slight little puddle at the drain holes on the bottom.
Well, I was just told by someone on this site that you can use a low bleach to h2o solution to clean you roots, rather than h2o2. So assuming that washer bleach is safe, then the amount of chlorine in your tap water will do no harm. Though if you fear harm from this, you can let it sit for several minutes to 24hrs to evaporate some.
All in all you're well, just cut back on the watering maybe 2.5-3Liters or give another day to dry, always water in the morning when lights first turn on. Also, your RH is good for veg but you're going to have to get that down a little more when flwering.
