One question (or 20, somewhere there). i have a siphon overflow that is rated at 600 gph and a pump rated at 300 gph. i am planning to make a sump and beautify my tank by moving the skimmer down. i have a 10g and all i want to know is if i can cut down the overflows intake to 300 so it runs even with the pump and doesn't overflow the sump. can i just buy a valve to put on the hosing to the sump from the overflow or do i need a new pump??????
Will a valve disturb the siphon?
Please try to explain in simple wording ( bare with me, im only 14 years old!!!

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