I've already tried all the basic recommendations

[Lynnzer]

If your tank is glass you could try a razor scraper...I love mine, gets the toughest algae off and doesn't scratch the glass

Not so good on planted tanks with algae on plants, wood and rock etc

 

[CaptainBarnicles]

Not so good on planted tanks with algae on plants, wood and rock etc

No but I wasn't suggesting it be used on plants and rocks...

 

[Colin_T]

Looking at the picture of your tank in your other thread, I would say the issue is too much light and not enough plants to use the light.

If you add more live plants, especially floating plants, it will reduce the algae on the glass and ornaments. Water Sprite (Ceratopteris thalictroides/ cornuta0 is one of the better floating plants to try. If it grows too fast, you can plant it in the substrate where it turns into a lovely light green shrub shaped plant.

If you have the light on the back half of the tank, you should get less algae on the front glass.

If the light has intensity settings, you could try reducing that a bit. However, if you are adding more live plants, don't adjust the intensity yet. See how the tank goes with more plants. If you don't want to add more live plants, then reduce the intensity.