Hello, I’m joining here from australia

[Genna]

I just set up my new (first tank since I was a young child) 150litre (just under 40gallons I believe) tank. I also got 2 smaller tanks with it which are 62 litres and 45litres. 
I should be adding fish in about 2 weeks once I’m back from holidays. I have decided on the types of fish I want but I am unsure on the quantity of fish I can add to the tank.

I know having the tank in front of a window isn’t ideal but I don’t really have space for it anywhere else and there are windows and large glass doors everywhere, this window lets in the least light. To make up for all the natural light I don’t have a light in the tank. I’ve had water in the tank for about 2 weeks and live plants in the tank for about a week and there have been no signs of algae so far. I have 2 internal filters and a heater in the tank as well hidden in the corners behind plants. There is 35-40 live plants in the tank, it looks like it takes up a lot of room but in reality it’s a fairly deep tank and the plants just cover the back part of the tank in a thin line, a bit thicker in the corners.

for the plants there is a specialty plant substrate with some black pebbles on top and the sand substrate is in most of the bottom of the tank because one of the fish I want are corydoras (wanting both peppered and albinos but unsure how many I want) and I read and watched some videos that said a sand substrate is best for them.

not sure how filled the tank should be like how much space should be between the water and the top of the tank so if anyone can help with that? There are glass lids on the tank under the wooden top as well so fish can’t jump out or hit the wooden top. 
there are 5 different types of plants, I’m not sure if I need a larger quantity of plants or more variety? I will be getting caves as well before I get the fish so the front won’t be so empty.

I live in Australia and it’s hard to find heaps of different types of plants for reasonable prices near me. Fish I can get what I believe is really cheap though.

 

EDIT: the fish I’m wanting are angelfish, kuhli loaches, bristlenoses, corydoras, and possibly some Platys. 
im planning on adding the bristlenoses first, then the platys if I decide to add them, then the kuhli loaches, then the corydoras, the the angels. 
I know corydoras and kuhli loaches have to be in groups so I would need at least 6 of each of those but I’m not sure how many I should get of the other types of fish or if I should get more than 6 of those. I would get them all pretty small and if there are issues with aggression or anything I have the 2 spare smaller tanks I can separate them into and I’m planning on using my 60litre tank as a quarantine tank

Edited December 17, 2021 by Genna
Adding the types of fish I’m wanting

[lefty o]

welcome to the forum. as for how high the water should be, thats personal preference. i like them maybe 1/2" down, others run them 1 or 2" down. its all whatever looks good to you.

[Flumpweesel]

Welcome, I take my water to the top of the visible glass (there is a plastic rim about 6cm ish that holds the lid ) because it is at eye level when seated in my living room and I don't like the brightness from the bulbs without the water filtering it.  

As you are using natural light you don't need to worry, if it has a well fitting lid jumping is less of an issue so as already said its up to you. If you do lower your water level though don't forget measure to the water line to work out your tank volume for water treatments or meds.  Happily its easy maths in metric 😉. 

[Guppysnail]

Welcome. The quantity of fish is dependent on what type of fish you are getting. Adding them should be done in stages to allow your bacteria to catch up. Quarantine  your new arrivals before adding. Irene does a great you tube video on making a quick inexpensive qt from totes. If you should need to treat with medication in a 40gallon it’s much more $$$$ vs the price of the tote setup. If you post your fish choices folks here are glad to help with quantities compatibility and who should be added first to ensure a peaceful tank. 

[GameCzar]

Welcome!  

[Atitagain]

Welcome to the forum!

[Patrick_G]

Welcome! It sound like you have a nice setup! Our house is the same with windows or glass doors everywhere. It’s hard to find a spot that doesn’t get sunlight in our living room. I still find it’s best to use a light because keeping a tank algae free is all about a balance between light and nutrients. With an electric light you can use a timer to achieve this.  Check out @Daniel’s journal on his historically accurate low tech tank for tips on using only sunlight.