Tankload of questions (long)

Several questions for all of you today. Any advice is appreciated.

At a small wedding I attended last week, we were given a betta along
with all the basic supplies as the table gift. First time I have seen
someone do this, but in his case it is appropriate as the groom is a big
fish fanatic (over 1000gal in tanks, with his family including the likes
of a lungfish, stonefish, buttikoferi, waterdog, oscars, lionfish,
electric eels, rays, and an alligator named Fluffy) and works at an LFS
to boot.

The fish themselves were given in vases along with gravel, water
conditioner, and food, so the basics are taken care of. While he has
been in the vase, he gets a 100% water change and gravel rinse every 3 days.

I've decided to move the betta to a 5gal tank, (possibly an Eclipse Hex
5,) and give him a few mates, most likely 5-6 neon tetras.

Question 1: Is a half dozen neons too many for this tank, based on 1"/gal?

Since I brought the betta home, it has not eaten at all. I have tried
Splendid Betta pellets (that came with the betta), Tetra freeze dried
blood worms, (specifically marked as being good for bettas,) a piece of
frozen blood worm, a piece of Sera Vipan staple flake food, and 1/4
cooked pea.. He won't eat any of it. As well, even though I fish the
food out of the bowl after 15-20min, the gravel rinsings show copious
amounts of waste.

He does move around the bowl, responds to me when I am nearby (but only
when looking from directly above), and has been blowing some bubbles.
Fins are not clamped during movement, and no disease indicators (other
then a tiny gray spot that has since shown up at the base of his dorsal
fin,) and becomes more active if I move him next to one of my other tanks.

Question 2: I know bettas can go a month without starving. Should I
just not feed him for about a week and see if he changes moods? I
realize that the double move (LFS to wedding to home) was likely very
stressful.

Now, on to the new tank. I have several tanks of which I can pull
cultured gravel from. Well, all except Marty's (my 2.5" buttikoferi)
tank.. He's liable to have it spread all over the tank within an hour!
However, none of the colors match what I want to use in his new home.

Question 3: If I were to say, put some of the new gravel in a cup
inside one of my current tanks, how long would it reasonably take to
have enough bacteria attach itself to be able to jump-start the new
tank? As an alternative, would it be easier to temporarily install a
corner filter filled with cultured gravel?

Question 4: The only experience I have with a biowheel is in my 75g
tank which had the wheels from day one. Would soaking the new wheel in
one of my established tanks do more than what I asked in question 3?

Now that I mentioned Marty, it brings me to my next question,
specifically feeding.

If I were to dump a whole container of food into his tank (10g until he
grows a bit more) he would probably eat it in 20 minutes. Voracious is
an understatement with him. I feed him once per day, starting with
Tetra mini pellets, then a few flakes, then some freeze dried blood
worms. I know that you should never feed more than they can eat in a
few minutes, but does this include when he's eating like a starved
lunatic? I put in the food in small amounts, of which he always eats in
about 10 seconds flat. Several small pinches (5-6 at a time) of the
pellets, a couple of flakes, then a few bloodworms at a time. Although
sometimes he slows down during the bloodworms, he usually is clamoring
for more when I end the feeding.

Question 5: In a case like this, how much is too much?

Marty is truly a creature of habit. He expects his one big meal a day,
and if you try to feed him at any other point in time he'll ignore it.

(Last question now, I promise!)

When I am cleaning the smaller tanks, it is hard for me to do a proper
cleaning without removing too much water. Specifically, cleaning the
gravel in the 10G is a royal pain. Normally I only get half the gravel
done before I hit the water limit. This is with a manual siphon. Using
a Python is not an option, as I can't get suction running the hose down
a flight of stairs, and the sink on the same level doesn't allow me to
get a good seal to get any suction.

Question 6: Any recommendations on better ways to clean the gravel? I
ask because this problem may be magnified with the 5g tank coming later
today. Should I look into a lower powered battery operated siphon?
Should I rotate scooping portions of the gravel out and rinsing it? The
10g has a little under 1" of gravel at present, with some areas deeper
than others, thanks to Marty's hole digging and plant rearranging antics.

Thanks in advance for your advice.