This may be obvious to some, maybe some can benefit from this.

I find that most of the algae cleaning instrumments sold in pet shops are expensive and ineffective.

The most useful tools I have found to date:

For cleaning and scraping algae and other unwanted debris from the glass sides of the tank, a plastic putty knife from the hardware store is the best so far, and only 98 cents. Or a small razor if you really have some issues.

Plastic Putty Knife Scraper

In the same aisle of the hardware store, they will also have some stiff bristle or wifer brushes. These are good of cleaning and scraping tank decorations and ornaments.

3 Brush Set