Firstly, the pump is not a sand filter system. The pump is the one with the motor attached and it pumps water not sand. The large round tank is the "sand" filter. You would have to find a skimmer made for vinyl pools with gaskets. It attaches to the wall of the pool and is seen "hanging" from the outside of the pool. The type of pool and equipment have no factor in choosing a skimmer.
another good way to go is the Dragonfly Super skimmer this is a floating pool skimmer and only requires a hose to connect it to suction
A pool skimmer is generally built into the side of or around the top of a swimming pool in order to skim debris from the surface of the water. A pool filter is built into the plumbing in order to filter fine debris from the water itself.
If you have more than one skimmer, close the valves for the ones you aren't hooking the vacuum to.
Determine how many gallons of water your swimming pool holds. You will also need to consider what size filter that you have. If you have an undersized filter to pump it can create filtration and circulation problems. Be sure to look at the turnover rate for your pump and filter that you are considering. If you have an aboveground pool most pump and filters are sold as a pre-sized set.
Use the main drain when backwashing, rinsing, or vacuuming. Use skimmer all other times to filter.
Empty the skimmer baskets and the basket that's attached to the pump. Then backwash and rinse the filter.
I have a backwash setting on my sand filter. You can also add a sand cleaner in the bottom skimmer of the pump. After backwashing, it is recommended that you also rinse the head.
After the filter has been backwashed, the filter valve is switched back to filter and the DE is added to the skimmer. The amount of DE to use should be shown on the filter and depends on the size of the filter area. The DE should first be mixed in a bucket with water then poured into the skimmer with the filter running.
How do you know that the main drain is plugged? When was the last time that you back washed or cleaned the filter? If there is no flow at the main drain - check to see if a valve has been closed or adjust the variflow valve in the skimmer - located at the bottom of the skimmer- if you have that type of skimmer. Also check the pump basket - it may be full of debris.k
Filter probably clogged with sand, leaves or dirt.
The best way would be to unplug the swimming pool filter, open the drain valve on your pool filter turn the pump back on and drop the water level to the desired level about 2 inches above the skimmer.
Adding algae control to the pool skimmer helps to disperse the chemical and coats the filter media.