There are basically 2 classification of “bad feng shui energies”: “visible forms形煞(峦头)” and “invisible energies 气煞(三才理气)”. Visible bad energies are easy to understand, what we can see e.g. facing T-junctions, convex roads, constructions etc and “invisible energies理气” are derived from classical feng shui theories like 三元, 三合, 玄空,卜卦, 挨星 and many others.
One misguided critic may “think” that feng shui cures or enhancements must be “sophisticated” like those commercial feng shui products that were sold by masters or shops that burn holes in your pocket. They seem to think that by putting “more” commercial feng shui items and the more pricey it is the better are the effects! Few even mocked at the use of plants, pebbles, door mat, mechanical music box, paintings, clock, air-condition, wall fan, curtain colours all which are ordinary household items without even look beneath the studies of classical feng shui principles. Please don’t tell me in today’s modern society one still wanted to use “bagua mirror” where an ordinary mirror will suffice?
Skeptics past judgement on the used of ordinary household items without realizing that items selected by masters of feng shui did applied at least one of the 5 Main Classical Feng Shui Cures/Principles/Functions:
b) block 挡
c) dilute 化
d) fight 鬥
e) avoid 避
Household items that were used as feng shui cures or enhancements have to fufill certain criteria like 阴yin 阳yang，五行 5 -elements， 八卦象数 bagua symbolism & computation e.g. bright objects are yang, “9” scented candles in iChing represent 离卦 fire-element, 8 whitish pebbles in certain manner form 艮卦 Earth-element, having “4 fish” in the tank is 阴yin and having “9 fish” is 阳 yang, colours also have it’s own representation “pink”, “purple”, “orange” “red” are “symbolic” to “fire”. The true test is know when to use what items, for which relevant sectors and what invisible energy that you want to rectify or activate? Sounds very abstract isn’t it. This is the short version already, feng shui is not “Science” and one can’t view it purely from sole logic or rational perspective!
Let me try to make it easier by simplifying it with real-life examples. “Principle A-遮 Hide”; if one window is overlooking an on-going construction or expressways one can simply “hang some long stem creeper plants” to “遮 HIDE” the bad view. You may think that this is somewhat a “self consoling behavior” but it is not! It does “diminish” the bad view and effects brought from a construction site. Noticed that Singapore likes to plant a lot of trees along the expressways, besides looking good it does reduces the “noise” from expressways. If one dislike plants because of mosquitoes, one can use blinds or curtains, with matching shape and colour to “fight 鬥” (Principle D) the bad energies depending on the “window orientation”, but i strongly advised against it.
More often than not feng shui masters use a more “peaceful and amicable” solution to cure the bad energies under “Principle – C dilute 化”. It usually takes the form of “通关” to resolve 2 conflicting elements”. The rationale is simple if the afflicted sector is caused by “the clash between fire and metal”, then “earth” element is the legitimate mediator. The reason got to do with the 5-Element production cycle which states that fire produces earth and in turn produces metal. So earth element is the perfect go-between to dilute the confrontation. Thus ordinary “earth” element representative objects could be used e.g. ceramic, crystal, pebbles etc. This principle is similar to 八字 Bazi teachings.
Principle B-block 挡 literally means block the bad energies from coming in or prevent positive energies from flowing out. Take for instance your bedroom door is 180 degree directly opposite a toilet door then one should have something to “block” the 2 energies from colliding or conflicting with each other. The simple solution is to use “partition” in between thereby fulfilled the principle of “block”.
Lastly if the house or office is really beyond redemption …the best way is not to engage a 2nd feng shui master for a 2nd opinion but to make a “run” for it i.e. “Principle E-avoid 避” (三十六计 走为上计) escape, sell away your house! Don’t throw good money after bad, just like any prudent investor. So sometime feng shui is common sense. Unfortunately common sense is not so common for some.