Undergravel Plenum

I just read that a in order to culture nitrate eating bacteria in your tank, you need a plenum. I have a few undergravel grates, can i put them under my crused coral and use it as a plenum to lower nitrates??

 

Where did you read that? Live Rock will go a lot further towards reducing nitrates than an UGF will.

 

well its not really a ugf anymore, its just used to create a low oxygen pocket for the anaerobic bacteria

 

the problem with your idea, is that you have crushed coral substrate, which is basically gravel there will be too much water flow unless you have like a 2 foot cc bed

edit: 2 feet is probably a overdramatization but it will need to be really deep

 

i recommend you get a fuge, or setup up a remote deepsand bed.

you want to have a stable bed that you can disconnect from the main tank incase something happens and that will be out of reach of things that can stir it up down to the lower levels

 

in the idea i read, they didn't have the holes, would it work w/o the holes on my grate to practically eliminate flow

 

Plenum's are a good set up had time not been such a huge factor when I had to replace out 180 with a 90 in a day I would have set it up as a plenum..
Now that being said you from what I have just read are not near close to build a plenum , Do some research and ask some questions there is more top it then a 1" void under a plate and the sand size is crucial you have to have the proper sizes in proper depth and there is not a one size fits all deal takes 3 and screen between the different stratas of the sands sizes . Nothing can be allowed to ever burrow or dig in the sand but a inch or so. Hence the screening of the layers.