Have to disagree. The amount of rock depends on the rock. There are all kinds of "rule of thumb" about rock. 3/4 to 1 1/2 lgs per gallon and up. The real factor on the rock is how open and popurous it is. LR like Tonga, is more pourous than say Fiji, so it has more surface area and therefore can harbor more beneficial bacteria which is the reason for the LR in the reef tank (plus its nice to look at) With the sand there are lots of opinions on a DSB (deep sand bed) I would suggest you do a search here on "DSB" and get ready top read. One of the main issues with a DSB is that after time, they become saturated with phosphates and junk and can cause a tank crash once they reach max saturation and start leaching back into the tank. The DSB does have different levels that perform different tasks as far as de-nitrification etc. They do have a bennifit and purpose (issue is longevity)that goes beyond asthetics. Do a search and be prepared to read. This way you can make your own informed decission as the opinions run the gamut and can be quite a hot point for many folks. You could also run a
shallow sand bed SSB, which is basically just for asthetics. Its easier to care for anf replace if needed. But it wont have the different filtering of a DSB. See where Im going? It really is best for you to check it out make make a decisiion based on what you find and want concerning the subject! There is the BB (bare bottom) method, high flow and no substrate or even a
Faux sand bed. The BB was generally started to help maintain as nutrient poor water as possible for a system that is dominated by SPS coral as this type of coral is from the fore-reef and in nature lives in high light, nutrient poor water. It aids in the coloration of this type of coral cause excess nutriants will cause the algae living in the coral (which also gives the color) to turn brown.
Also on a high flow system that is designed to get the detritus to the sump/skimmer and has a high quality kick butt skimmer, you can use less rock. There is room for you to make the aquascaping the way you want it. You dont have to have the box full of rocks look. BUT, more rock=more beneficaial bacteria=more filtering capability. The bacteria handle bio-filtration and the skimmer emoves disolved solids.Hope that helped and didnt just make you more un sure...
R
