Thanks for the kind words. Unfortunately the 40 breeder is a 36" tank. There really isn't a larger tank with the same footprint. 75 and 90 gallon tanks are 48" tanks, 120 and 150 are 6 foot tanks and bigger than that are 8 foot tanks.
There's nothing in the fluval line between a 405 and a FX5. The 405 is $140-ish, the FX5 can be found for $180-$200. So in terms of price, there isn't a huge gap. In terms of filtration ability the FX5 eats the 405 for breakfast.
If you'd like to save a few $$, take a look at the Rena XP4. It's a solid filter and will give you a clean turtle environment up to about 100 gallons. Again, the XP4 is AROUND 170. The FX5 is $180-200. I have both. You can put the XP4 inside the FX5. When the FX5 is done having it's 405 breakfast, it went and had the XP4 for lunch.
As for PDF's maybe you didn't see the link I forgot to post... Check this thread out it has the adjusted turtle appropriate sizings and how to set the filters up...
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