So first you need to choose the size of youre tank i choose the 180L tank. But every tank will work just need to set another plumbing setup/ and all whats in the tank to have a balanced tank.

So if you are ready for the next step (And please dont add any plants or fish or they die bc the water balance isnt in the right balance.

The indoor and ourdoor tubes are the one that you see now.
For now forget the output tube, lets start making some filters on the input tube. Waste filters as it said remove the waist of youre tank it means poop/pee (yes fish can pee) and if its in a good amount of filters it helps to provide algea.

Then i started with the Power Generators (I always forgot these so thats why ;)) They are needed for youre filters/ co2 and O2 stones. All what needs power.

As third i use always a nutrient injector it helps to grow and stay healthy for the plants, so for this tank ive used one for this bc the bottom of the tank has a + amount of nutrients it isnt that needed.

As last bc i dont have tropical fishes, and the tempratures are without a heater 20 its for me not a needed element. But if u want the more tropical fishes and plants u maybe need to put a heater in it in a 180L tank i should do one in it. But then the Plumbing is done, so we have to connect with our output and then to the funniest part!! Decoration/plants and fishes <3

So i just always start with the decorations: First all the larger plants in the background and form larger plants to smaller and sometimes a stone or wood object etc... between the plants not too much...
Later i do the decorations in the front the stones/wood objects or even some small special plants i like too much.
Also other equipment needs to be placed: I always use the oxygen and co2 stones to regulate it fast if its goas not what i wanted. Also a sponge filter is a thingy to not forget i used the smallest one bc for the more and better view. A sponge filter has also some extra good thing it makes oxygen and nutrients and is a good algea place to eat for the fishes (Especially the newborns).

And then its time for putting the fishes in the water :). Remember chek youre water stats to make sure they get a good start. Choose fishes who can together with all the stats they have. Some are agressive then dont put another agressive fish in the tank or if u have a larger tank you can do it. Sometimes agressive fish eat others. Maybe its the size of the tank or the amount of fish.... Think before you put youre new fish friends in it :)
Goodluck, remember im not a pro in this but this is how it works for me so i thougt its maybe a inspiring guide to make for others :) Questins or feedback please give it i love it <3