Help install new sand filter tank

[bensmail]

I ordered a new sand filter tank this year to replace my cracked unit. The instructions are terrible. Only one picture and it's not even my model.

Questions. There is no markings for how high the sand should go and nothing in the directions. It's a 110 lb sand tank but I have no way of knowing how much is 110 lb. I plan to use my sand from the old tank, it's only been used for about 2 months.

Also there is a small clear tube with a plastic filter cap at the end. No idea where this should end up after install.

 

[woodyp]

You can Google how much either a one gallon or 5 gallon bucket of sand weighs. Should get you close enuff. What size was your old filter?

 

[bensmail]

Well.... I looked it up and my last one was the same size from a different MFG. That makes it easy. But now that I think about it I believe I only put in 100lb (two 50lb bags)

I'm not sure how critical it is. Is it not a problem to put a little less sand in?

Any idea what that clear tube is for? I assume it should be above the sand.