I currently have a 40 gallon breeder turtle tank that has some fish inside of it, along with a 15 gallon column tank. I'm about to start working on either a 75 gallon tank or possibly a ~100-120 gallon tank that is more wide for my turtle once I move, but buying all of the equipment needed now and most especially working on the driftwood basking area that I have for the bigger tank size.
Algae is always an issue, and when it comes to my turtle tank, a big issue as there is additional lighting for the turtle that just promotes the growth of it all over the driftwood and glass walls. I've either manually cleaned it with a rough sponge, or in some cases I let the Malaysian Trumpet snails do the rest of the work in areas that I can't see (like the driftwood, or in spots that I just can't get due to how the tank is against a wall).