Algae grows in tank and filter tubes of my Rena Filstar Filter

I am using a RENA XP-3 on a 55 gal. turtle tank (2 4" red eared sliders with 2 algea eaters), since switching from the factory supplied filter media to your "super activated carbon pouch" and your "dual density micro filter" along with the factory 20 ppi and 30 ppi foam and bio chem stars, the algea grows rapidly, the tubes are coated on the inside and the water stays green. The factory media kept it unbelievably clean. I clean the foam and micro filter every two weeks, with tap water, replace the micro filter and carbon pouch monthly. The basking lamp is over a homemade basking area, NOT over the water. the tank light is on 10-12 hrs. a day, there is no direct sunlight into tank, (windows within 6" of tank but shades drawn). Is there a better filtration media to prevent algea growth? any ideas? They are due for a bigger tank, but I want so solve the algea problem before I invest in a bigger tank.

A: Algae blooms when it has enough food and light to grow. Alagae spores are in the air and on anything in the tank. Turtles throw a lot of waste into the tank providing food and of course the tank is not in the dark so the algae grows. Although the the factory setup worked for you when you first set up the tank my guess is that as the turtles have grown the amount of waste has grown beyond the point of the filter's capacity to remove it and/or break it down. You can alway go back to the original factory setup by buying BioChem Zorb and the standard Micro Filters but my guess is that it won't be the same since the turtles are no longer the same. Here are my suggestions in order of importance:

1. Test the water for Phosphate and Nitrate. If it is present then you'll need to remove this from the water either by doing a partial water change or adding additional media such as PhosZorb and NitraZorb. This provides the food the algae needs to grow.

2: Beef up your biological filtration by using Pond Care Biological Filter Booster.

3. Use something like Pond Care Algae Detroyer Advanced or Algae Fix and just kill the algae. This is as easy as it gets.

3. Buy a UV light and kill the algae that way.

4. Get an additional Filter or larger filter with more capacity. Remember, filter ratings are based on an aquarium with an average amount of fish and not turtles.