It will probably take, depending more on the size of the follicles. If they're in the 10-15mm range, it has a chance of not doing anything. If larger, it has a great chance of taking. 500 grams is fine for a breeding male, as long as he's still eating.
If your goal is to produce lemon blasts, don't throw another male in there. Also, I'd give the female at least 4 weeks off. Let her follicles grow in size a little more. If her follicles are already at the 20-30mm range, then most likely the lemon blast got it done, and it won't need another lock... Good luck!
--Oh, also, if you want to have the lemon blast be the sire with her, it's likely not a problem to give him and her 2-4 weeks off, then pair them again. Give her time to build and develop those follicles.