Newbie with Questions for Opae Ula (volcano shrimps)

I got one of those self-contained ecosystem for shrimps. Upon receiving it, I find that the container a bit small for the shrimps. I googled and found to my horror, I found that the closed ecosphere I always wanted one is a torture chamber.

The container I have is an open system and comes with instructions to feed once a week so it is not a torture chamber. But still, I am uncomfortable with the size of the container. I read and read and read. There is so much info out there that contradicts itself - like size of suitable tank or whether filter or air pump is needed.

After thinking through and having a sleepless night, I decided to move the shrimps to a larger tank. With the help of some kind souls (for a fee of course - my sis is like saying you spend HOW MUCH on the tank set up), I moved the shrimps to their new habitat. From what I researched, there are 2 ways to know whether the shrimps are happy or note - a)whether they are red and b)they reproduce successfully. On the first day, I have decidedly pale colorless shrimps in their own container although they look active and lively. Now quite a number of shrimps turned very red like their wild counterparts and with the exception of 1 shrimp, most have pinkish tinge to them. I have 22 shrimps and I feel responsible for them.

Hopefully with the set-up, the shrimps can live comfortably and has a sufficient community to socialise (?). I think the original open-system I have is not that bad but the size of it makes me uncomfortable. But the closed ones are really no-no. I really cannot comment on the small open-system in plastic containers but they are certainly more humane and after researching online, I tend to lean towards the conclusion that they are ok but not ideal (No flaming please)

I cannot post the pictures as I am newbie but I have uploaded them to my album.

Would some kind souls kindly help to answer my queries:

a. My tank has several maromi with the largest 5 cm or bigger in circumference (never really measure it). The shrimps love them. When first introduced, the shrimps pounced on the biggest one. Quite scary to see the whole lot of them pounce on the big maromi at once. They also like to hide under the large maromi where there is a hiding place against the sea shells. The problem is that my maromi is growing and now quite....flurry. And I itch to take them out to wash time. Being such a new tank, I loath to do so as I don't want to stress the shrimps. I have several maromis housed in different containers. I am wondering whether I could rotate my maromi on a monthly basis so that I have the chance to roll the maromi around and re-shape them and allow them to recover from the shrimps grazing. The problem is that the maromi are housed in different types of water. Maromi only containers used only mineral water while the shrimp tank uses brackish water. Would the shrimps die from the rotation of maromi in different water?

b. There are not many hiding places for the shrimps except for the giant maromi which lean against the seashells forming a natural cave. And I believe that the shrimps need some places where they feel safe. I am thinking of introducing those clay breeding pipes/barrel a few months later (see picture in my album). The barrel one I have has a green stripe beside them. Are they safe for the shrimps? And how soon can I introduce them? I assume it would be months later since the tank is still new and I think the shrimps would need time to settle.

c. If I find that I need to take something out of the tank, what instruments do I use? Disposable chopsticks? Stainless steel tongs?

d. Some shrimps started to molt. I read that they normally find a quiet place to molt as it is dangerous. But how come I see one or two of them molting but still swimming happily? Shouldn't they be hidden somewhere?

e. I observed one very, very dark red shrimp curled up like a tight C and then suddenly straighten up and move off like a rocket? What exactly it is doing?

f. I did try to feed them after one day in the new tank. They don't seem interested but eventually finished it. Is it okay I quit feeding them for 1-2 weeks until they are more settled as I understand overfeeding is no. 1 death for the shrimps?

Thank you! I probably have a lot more questions down the road. I am still crossing my fingers that my shrimps would survive their new home.