NEW YORK ( TheStreet) -- The markets opened lower Monday but ended the day mixed.Even though Apple ( AAPL) is up 10% in the past month, Pete Najarian said on CNBC's "Fast Money" TV show that he still thinks there's upside momentum. He cited that there was heavy options buying in the September 500 calls. Steve Grasso disagreed, at least over the short term. He said that with the rally to $470, he would look to take profits near the 200-day moving average. He would again be a buyer around $440. Tim Seymour said the last time Apple broke through its 200-day moving average on the upside was in April of 2009, and that he doesn't think the stock will be able to break through on its first try this year. He added that he was a seller at $505. Karen Finerman thinks the upside momentum will continue since investors still have about a month until the new iPhone launch on Sept. 10. Guest Collin Gillis has a $500 price target on Apple, along with a buy rating. However, he doesn't think the stock will ever get back to its all-time highs. Finerman said that if there's any trade on J.C. Penney ( JCP), it's on the short side. The company reports earnings on Aug. 20. Grasso said he sold Tesla Motors ( TSLA), but definitely wouldn't think of shorting it. Guest Dennis Gartman, editor of The Gartman Letter, said that between buying physical gold or the gold miners, he's a buyer of the miners. He added that it was the first time years it made sense to own the miners from a risk perspective. He said investors could gain exposure to miners via the Market Vectors Gold Miners ETF ( GDX) and exposure to gold through the SPDR Gold Trust ETF ( GLD). But he is avoiding silver because of the volatility. Najarian said he likes the iShares Silver Trust ETF ( SLV) as his way to trade the precious metals because the price fluctuations are typically more extended than that of gold's. F5 Networks ( FFIV) was the first stock on the show's "Pops & Drops" segment; it jumped 3% on Monday. Najarian said there's plenty more upside left.