yellow stained steps and a rusty skimmer.

[when_in_TN]

I searched the forum for getting yellow off of steps. Tried the vitamin C tablet and it did turn white. I tried it on the skimmer too and in some places it turned white but in other spots it stayed beyond yellow and it just looks rusty. There is also a line just under the skimmer that looks like rust on the vinyl.

Anyone know what's up with that rust?

As for the yellow stains, do I have to treat all of the water or just kinda spot clean in places? Will whatever I treat with take care of the rust too?

 

[Texas Splash]

So the type of staining and effect of using vitamin C tabs indicate you have some metal stains (iron/copper). Metal is either introduced to the water via fill water (i.e. well) or sometimes from pool store products like and algaecide. Once in the water, metal can only be remove by exchanging the water or controlling what's in it with a sequestrant which helps to "bind" or contain the metal to prevent it from reaching-out and staining the surfaces. Sequestrants are not one-time products though, so they must be reapplied periodically. You can spot-clean as needed, while some pools with large staining issues all over may require an Ascorbic Acid treatment.

It would be nice to know where the potential metal came from so you could plan accordingly in the future (example, use metal-free replacement water, remove rusted hardware, etc) . The good thing is that your water appears to still be clear, so watch your FC and pH to keep the pool algae-free and help prevent a chemical reaction. You might also benefit from the TFP Pool School - Metals in the Water and Metal Stains page. Hope this helps get you started.