Thanks so much for your posts. I appreciate your willingness to help!
Here is what I know so far. The tank is a 65 gallon tank. The tank at the bottom is supposed to be a refugium? But it filters the water too? Not sure how that works but, the water drops from the tank down to the smaller tank, and then it gets pumped back up.
There is a lot of red and green algae in the refugium tank and the red algae forms almost like a carpet effect on the sand in the main tank. Not sure if that's healthy or not, but I've never seen in in nice tanks so I'm assuming its not.
The tank evaporates water pretty fast, we have to add 2-3 gallons of RO water every week. The water is dripped in.
There is supposed to be a protein skimmer In the smaller tank he said but something broke and he's getting that fixed. The tank was in the shape it's in now with the skimmer in place. Not sure if that information helps or not. I am not 100% sure of what the skimmer is supposed to do or how it helps the environment.
I will try to get to a LFS today and get the water tested to get a baseline on the tank. I will post the findings as soon as I am able to.
Thanks!