X2SR and X2S off same 3/8 input hose? Siphoning issues?

[Green1181]

Hey everyone, looking for a bit of advise. I have just purchased and X2S for my 350L tank and an X2SR for my 750L. I could only manage to get one 3/8 line fished up through some existing conduit in the house to go to the salt water storage tank. I was planning on running both pumps off this 3/8 line but have been reading about the X2SR siphoning. Aside from a check valve, which i've read isn't the most reliable, does anyone else have any other suggestions? I am thinking of maybe having both pumps run at the same time but I don't know if this is possible?

 

[blaxsun]

Nothing other than a check valve. I probably wouldn't run both pumps at the same time to ensure each has full access to pull water for water changes.