Okay tomorrow I will get a but load more cl and try the process again. Also I have enough idea of condition of the sand pump it's always around 29-30psi doesn't move from there.
I did by the bottle of filter cleaner and run it through it.
By deep clean I am referring to this procedure

- not a product
This post will walk you through the anatomy of a sand filter, and then provide a video at the end for how to deep clean your sand filter. The filter used in the photos and videos is a Hayward S180T top mount sand filter. The images are of a similar filter. Obviously not all filters are...
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We’ve had people who inherited pools that thought they had sand when in fact it was some alternative media (like nasty filter balls).
Opening it up to give a deep cleaning also allows you to check & ensure the sand is at the proper level.
Not a bad idea with unknown equipment.
Also confirm that the gauge goes to zero when off - if not, its time for a new gauge.
Backwashing should be done when psi rises 25% over clean pressure so it’s important to have a functioning gauge.
Too much backwashing can be counter productive.
Once you’re following all the
SLAM Process
protocols as outlined and have confirmed your sand & filter is in decent shape you can use a little pool grade DE to help “assist” your sand in collecting the finer particles that persist as you get to the “pool owner patience” part of the slam.
More about that here
A clean pool filter will increase the efficiency of your pool! ... your filter are to backwash it, clean the manifolds and grids, and add new DE.
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You want to be in the final stages with all the other bases covered before proceeding to adding any DE. As mentioned in the tutorial you can just add when you’ll be around to monitor psi & omit it when you won’t as it’s washed away by backwashing.
Slam level fc is to be maintained until ALL 3 end of slam criteria are met.