The first picture looks like you are getting some green hair algae, but I am not so sure about the brighter green stuff on the sand bed. I'd assume that this is an algae bloom caused by high nutrients in the tank. I'd try to manually remove as much of the algae as you can while performing a large water change. You can scrub the rocks with a toothbrush while holding the siphon over that area to remove whatever comes off as well as the surrounding water. After that is done, turn the lights off on your tank and cover it with a blanket or something for 3 days. This will starve the algae of the light it needs to survive. After the three days, you have to do another large water change (at least 30%) to remove nutrients coming off the dying algae and remove whatever remaining GHA that you can. I would look into ways of bringing down the nitrates and phosphates in your tank as well, or this will just end up happening all over again. Running GFO and carbon in a reactor has worked well for me. I use the BRS dual reactor for my tank. If you cannot add any equipment to your tank right away, another approach is using bacteria to out compete the algae for the nutrients. Dr. Tim's Aquatics has a product line that has worked well for me also, it is called Re-Fresh and Waste Away. It is a natural way to remove nitrates and phosphates from your tank. I think I have heard some folks having good results with Microbacter 7, though I cannot attest to it because I have never used it. Keep up with your tank husbandry (water changes, filter maintenance, testing) and things should get better over time. Unfortunately, it didn't get this way overnight so it won't clear up overnight either. Be patient and diligent, and you should start seeing some results. Don't give up! Your tank is very young and there will be more bumps in the road along the way. Just do the best that you can and try to enjoy the ride. Good luck!
