Is it my sand filter?

[forAK]

I've been battling cloudy water since I got this pool running in June. I got it used in May from a guy who had it for the past 8 years.

It's grey/bluish cloudy, not green at all.

In fact my numbers are as follows:
CYA - 30
FC - 10
PH - 7.6
TA - 70
CH - 210
I had put new sand in my filter, Hayward 220. I did not backwash the sand at all, just threw it in there and let her rip. This is what I'm thinking is my problem. I didn't backwash. Now, almost 2 months later and I still can't see the bottom of the steps! I tried adding DE to the filter and my pressure didn't even raise. I let it sit for a couple of days and then did a backwash. Cloudy water came out....and kept coming. I then changed it to rinse and now sand is flowing out! What the heck is going on? I'm thinking that I'm not even filtering my water at all. Why would sand be coming out during the rinse cycle. I do have a constant drip when I am in filter mode, slow but constant. Could the multi port be shot? Do I need new laterals? I'm baffled......

[Watermom]

What size is the pump (hp) and what size is the filter? (How many pounds of sand?) Also, what is the volume of the pool?

[forAK]

I've got a 1hp Hayward single speed pump and Hayward s220 sand filter with roughly 210lbs of sand in it. The pool has roughly 17K gallons of cloudy grey/bluish not pretty water.....

[JimK]

I took a quick look at that model and Hayward states that it requires 250lbs of sand. Could it be that not having enough sand could cause the problem?