Algae Problem (Sanitize Robot?)

[johnboy85]

Hello guys, I have been having what I thought was a pollen issue for the last few weeks. I would vacuum the entire pool clean but it would just go back to being covered in a yellow substance the very next day. I even bought a robotic vacuum (Dolphin Oasis Z5) to help keep the pool clean.

I read somewhere online that pollen will not stick to the sides of the pool so now I think it may be yellow algae.

Here are my levels:
FC 3
CC 0.5
CH 325
TA 120
CYA 80

It looks like I need to get my CYA level down before I start the slaming process.
http://www.troublefreepool.com/content/128-chlorine-cya-chart-slam-shock

I was thinking about dropping the CYA to 40 but according to the pool calculator I will need to replace 50% of my water.

Here are the other issues that I am having. It looks like I may have black mold also:

Also Since I purchased this house there have been rust stains at the bottom of the pool and I have not been able to get ride of them using any add-on pool devices that delivers muriatic acid. Since I have to drain the pool 50% anyways should I just drain it completely and treat these rust spots with direct contact of muriatic acid? Is that the best way to address these rust stains? What would be the best approach to knockout these issues all at once?

Also I have read somewhere that you need to sanitize all your pool equipment/tools. How do you sanitize a robot where the manufacture says the maximum FC contact should be no more than 4ppm?

Rust stains:

 

[pooldv]

That looks like some plain old algae to me. A SLAM ought to take care of that. I would only lower CYA to 50 or even 60 and then SLAM at that level, Chlorine CYA Chart

You don't list PH, lower that to 7.2 before starting the SLAM, Pool School - SLAM - Shock Level And Maintain

For the rust, crush up some Vit C in a sock and rub it on the stains, it should lift the stain in a few minutes.

 

[johnboy85]

Thanks for the advice. After I slam the pool I read that you need to disinfect your pool equipment so you don't reintroduce algae back into the pool. Should I just through all my pool cleaning tools into the pool while I am slamming? If so, for how long? What would be the best way to disinfect the robot that has been vacuuming up this algae?