Ultralife Red Slime Remover works for me. I just post from another thread how to use it correctly, I will copy and paste to here.
1- Turn OFF Carbon creator or Carbon filter (Carbon will remove RSR)
2- Leave the skimmer On for oxygen, but take the cup off or let it drain back to the sump by the hole from the cup. You need to raise the skimmer up a couple inches and open the output valve completely. (Do not skim away of those RSR)
3- Skimmer has to overflow and it ALWAYS overflow. If it is not overflowing after one night, that means RSR was out of your tank or something not right.
4- To stop the micro bubble from skimmer send back to display tank, You can put few black foam in the middle compartment between the skimmer compartment and return compartment.
5- For best result, after 2 days you can use the toothbrush to brush all the red slime algae from rocks and clean your filter sock daily.
6- The red slime algae will clean after few days depend your tank condition. You don't need a water change if you don't want it. Just turn ON your carbon creator and start skim out all of the bubbles to the bucket. (Don't forget to add saltwater into the tank while skimming RSR out).
Within 8 hours your tank will back to normal without water change, but with my opinion, I want change some water by clean my sand bed with some algae die off.
Note: I think the OLD salt mix causes this issue more than light, food, current flow. You need to find out what cause your tank has this issue, if not, it will come back and don't blame on Red slime remover doesn't remove completely.
Hope this help and good luck.
