high nitrates, algae outbreak, cleanup crew????

So I need some more help here. I have really high phosphates, and I have done two 25% water changes and still cannot get it below 160ppm. I just had a hair algae outbreak and I was looking to buy a cleanup crew to help get rid of some of the detritus and now the algae. But here is my question, will the high nitrates kill the CUC, would those nitrates also kill a lawnmower blenny, I have been wanting to get one since I set the tank up, but was worried about its food source if I didnt feed it enough, but now that I have the algae it would be perfect. I also though about a sand sifting goby? would the nitrates kill any of these three things? Help me out here