Tang size and how to prepare for a scopas

[nyji]

Hello everyone,
I am planning to have a Zebrasomas scopas and need some advice from people that have experience.
My current tank is only 100 litres (80x35x40 cm) and I want to upgrade to atleast 150 cm maybe 180 x 60 x 50 cm tank. I want to build d the hardscape dedicated to the scopas, so it fits its needs.
Current tank mates are very chill animals, Koumansetta rainfordi and Callogobius hasselti and they would transfer into the new home as well.

Is it really a good idea to get a scopas tang with that small tank size? It will be atleast 500 and maximum 800 litres!
I am not planning on adding that many fish besides those 3, maaaaaaybe some other small chill ones but I prefer having only a few. Main focus is on lps/soft corals.

Should I get a small scopas already (currently 100 litre, would buy it as a small fish) so I am sure it gets enough food/doesn't get lost?

I am able to feed it with nori algae as I got some chinese supermarkets in my area. But I could only feed in the morning and in the evening. I could get an automatic feeder tho.

Some more information:
The new tank would be ready in about 2-3 years! but I am a 100% sure it will be. It just depends on if I move into a new flat or not.

Thank you in advance.
Edit: title messed up, can't edit

 

[AydenLincoln]

Definitely hold off until you can get the much bigger tank. A tang isn’t going to be in 26 gallons/100 liters.

 

[Mr. Mojo Rising]

Please think of the animal happiness, not only yours.
It needs at least 400 litres very minimum, please wait till you upgrade to the proper size tank.

 

[nyji]

Cherry picked...

Please think of the animal happiness, not only yours.
It needs at least 400 litres very minimum, please wait till you upgrade to the proper size tank.

400 litres for a scopas tang as the final tanks sounds way too small... any measurements regarding length/depth? Maybe hardscape builds that are necessary?

Getting him early is off the table then. What about the rest?

 

[Reef's Philosopher]

Please think of the animal happiness, not only yours.
It needs at least 400 litres very minimum, please wait till you upgrade to the proper size tank.

So if i build a 5ft all in one 500l tank with an aio on the left which leaves the tank to 4ft to 4.5 i can permanan Keep a scopas also keeping in mind i fullfill its needs

 

[nereefpat]

So if i build a 5ft all in one 500l tank with an aio on the left which leaves the tank to 4ft to 4.5 i can permanan Keep a scopas also keeping in mind i fullfill its needs

What will the final dimensions be in all directions?