We have a 20 year old filter.
It looks very close to this filter. (Pentair 2000??) The labels have faded away, so I don't have any idea.

Everyday or Every other day, after I started managing the pool, i've been sweeping the pool floor to the deep end. The floor of the pool always has a thin layer of dirt? After doing that, I manually vacuum the pool. But after a couple of days, there is again a thin layer of dirt at the pool floor.
Is this is normal? How often do people normally have to vacuum the pool floor?
I know some people have automatic cleaners, but i'm just doing it manually.
During this entire processes. I'm in the middle of an epic yellow algae fight and i'm not really sure if i'm winning the battle or not. My current FC is around 12-14 ppm. I want to shock the pool, but i'm not sure if the filter will be able to actually filter the pool or not.
I brought out our pool man and when he came out like 2 months ago, he said the filter is fine, but he thinks the sand? or whatever is in the filter that cleans the water is leaking back into the pool. Today he came out and told me I need to replace the filter without really checking the pool. I'm not sure what he would even check, but he even claimed that he personally doesn't know how to replace filters. And gave me a number of someone else that does.
I'm tackling alot of pool issue all at once, and all these things are going to be really pointless if my pool filter isn't really doing it's job. Right?
Any suggestions? How do I know if my pool filter is actually working? What are the signs I should be looking for?
Can I shock my pool even if my pool filter is "kind of" working? Or should I address this issue first
It looks very close to this filter. (Pentair 2000??) The labels have faded away, so I don't have any idea.

Everyday or Every other day, after I started managing the pool, i've been sweeping the pool floor to the deep end. The floor of the pool always has a thin layer of dirt? After doing that, I manually vacuum the pool. But after a couple of days, there is again a thin layer of dirt at the pool floor.
Is this is normal? How often do people normally have to vacuum the pool floor?
I know some people have automatic cleaners, but i'm just doing it manually.
During this entire processes. I'm in the middle of an epic yellow algae fight and i'm not really sure if i'm winning the battle or not. My current FC is around 12-14 ppm. I want to shock the pool, but i'm not sure if the filter will be able to actually filter the pool or not.
I brought out our pool man and when he came out like 2 months ago, he said the filter is fine, but he thinks the sand? or whatever is in the filter that cleans the water is leaking back into the pool. Today he came out and told me I need to replace the filter without really checking the pool. I'm not sure what he would even check, but he even claimed that he personally doesn't know how to replace filters. And gave me a number of someone else that does.
I'm tackling alot of pool issue all at once, and all these things are going to be really pointless if my pool filter isn't really doing it's job. Right?
Any suggestions? How do I know if my pool filter is actually working? What are the signs I should be looking for?
Can I shock my pool even if my pool filter is "kind of" working? Or should I address this issue first