Originally Posted by
asharp13
http:///forum/post/3127178
How important is my sand bed??? Can I take out the majority of it and still have my tank be ok??? Also, if my LR holds the majority of the nutrients my tank needs, what affect does the algae growing on it have??? Will the algae kill those nutrients?? Therefore do I need the minimal nutrients comming from the sand bed???
The algae is growing from the nutrients that the sandbed is releasing when you do your water changes, the nutrients in the rock are more or less locked in place.
In being a reefkeeper, most of us strive to reduce or eliminate nutrients, they invariably do more harm than good.
In a reef aquarium, nutrients (aka phosphates, nitrate, detritus and so on) are a bad thing. You don't want to replace more than half the sand bed because you'll lose beneficial organisms like bacteria and microfauna like worms and pods and such.
If you can replace half the sand, like from one side of the tank, instead of an upper layer, that would be ideal. That would give the established sand time to seed the new stuff with beneficial organisms. Wait a month or two, then do the other side.
I got this info from an issue of FAMA a couple years ago where an individual with a huge aquarium was having algae and lateral line disease problems that was determined to be caused by phosphates and other nutrients locked in his sandbed and being released by the sand getting stirred up during WCs.
The writer in the mag had him do enormous water changes coupled with replacing significant portions of his sandbed every 3-4 weeks apart.
He also had the letter writer use Poly Filters in his filtering system to remove nutrients from the water column. They can get pricey, but they work.
You could use Phosban or some other phosphate adsorbent material in a mesh bag with water flowing through it, but most of these won't address nitrates and other nutrients.
His aquarium was something like 200g or so, so he did 1/4 or 1/3 of the bed replaced at a time, with such a huge amount of sand there was more than enough to seed the new sand in 3-4 weeks time.
Your case I say half and a longer wait because it'd be a bit simpler, and the longer wait lets the new sand seed better.
Its really rather radical, so if you can utilize the P word and stick with RO/DI - distilled water changes/topoffs from now on and see any algae die-off, that would be better.
As for your refugium light, I think a reverse light cycle with it is commonly acceptable.
Speaking of lights, have you replaced the lights of the tank yet? If not, don't replace them all at once, replace one tube a week to reduce light-shock on your corals.
Anyways, this info is given for you to decide what to do, just keep in mind the P word when you decide on a course (or courses) of action.
PS: if theres anyway you can "borrow" a lawnmower blenny and an emerald crab or two, thats another thing that would help while you're doing what you decide. Lawnmowers are supposed to consume hair algae, and emeralds go after most bubble. A few margarita snails and astrea won't hurt, but keep an eye on them if they fall, and big margaritas can bulldoze smaller rock.
