In regards to cost, IME this is absolutely relative to your location/area, as it relates to local trading or LFS's. If your area has a high volume of coral A, naturally the cost will go down as coral A is highly abundant. Conversely, coral A might be two or three times as expensive a few hours up the road. Naturally, prices vary far less for online retailers in regards to location. The only price varying I see from online retailer A and B is directly related to "name brand" corals or site reputation. A place like battle corals, WWC, Unique Corals, etc are "higher end" comparatively to something like aquarium depot, live aquaria, etc. That being said, you also get what you pay for. Unknown Acro A: $7 VS Super Duper Fairy Unicorn Princess Acro: (1) Arm.
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