Jess

I know it is a very daunting task but I would suggest you read through the whole thread if you haven't done so already. You will find all you need, and some, on these pages.

Plax bottles are one option, Netto shampoo bottles are another, graupner tank is another. I have used the 2 latter ones in my L39's and both work fine. The Netto bottles and Plax bottles are very similar iin configuration and I would choose one of these as they allow one tank to completely empty before the second tank starts to empty.

Good luck and happy building.

Ian