NEW YORK ( TheStreet) -- Here are five ETFs to watch this week.PowerShares QQQ ( QQQ) Investors holding QQQ will want to stay vigilant at the start of the week when the Nasdaq's well-documented and anxiously awaited rebalance goes into effect. A number of companies including Google ( GOOG), Oracle ( ORCL) and Microsoft ( MSFT) will see their weightings change. The firm, however, that most investors will likely have their eyes on will be Apple ( AAPL). After the rebalance, the tech goliath will remain the index's largest component. However, its weighting will be dropped by 8 percentage points to 12.5%. QQQ's performance could prove choppy over the short run as this readjustment takes place but I urge investors to stay calm. This fund remains an attractive option for tech-hungry investors. Guggenheim Solar Energy ETF ( TAN) The solar energy industry got a lift at the end of last week. News that French energy giant Total ( TOT) was planning to take majority control of SunPower ( SPWRA) sent shares of the American solar firm soaring over 35% on Friday. SunPower represents 3% of TAN's portfolio, placing it just shy of the fund's top 10 holdings. Looking to this week, industry leader First Solar ( FSLR) will be a major focus as it steps up to report its quarterly earnings performance. The company's results will have a major impact on TAN's performance. FSLR accounts for nearly 15% of its portfolio. First Trust ISE Revere Natural Gas Index Fund ( FCG) The oil industry was busy last week as a number of top integrated oil giants stepped up to the earnings plate. This week, however, it appears as though natural gas will be in the earnings spotlight. A number of companies comprising FCG's top 10 positions will report their quarterly performance this week. Firms include PetroHawk Energy ( HK), Stone Energy ( SGY), SandRidge Energy ( SD), Ultra Petroleum ( UPL) and Murphy Oil ( MUR). Other notable natural gas players companies such as Chesapeake Energy ( CHK) and Anadarko ( APC) will be reporting as well. As I've mentioned in the past, using FCG is a safer and more reliable option strategy for tracking the performance of natural gas than futures-based products like the United States Natural Gas Fund ( UNG).