If you're going to DL only once per week I'd recommend dropping the weight a bit and doing 5x5 or something similar if you think it won't interfere with your other training too much. You can add 10 lbs each week that way and cycle back as you feel you need it.

wv

Edit: if you want to DL once per week and add weight regularly vs. maintain

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Loose - http://www.merriam-webster.com/dictionary/loose
--1 b.(2) : having relative freedom of movement

Lose - http://www.merriam-webster.com/dictionary/lose
--6 : to cause the loss of

"To loose fat, one must simply unbuckle one's belt; to lose fat, one must tighten it." - wv