plastic scrub pads

[vfc]

The Rena XP 20/30ppi filter sponges should last just as long and probably hold more BB than pot scrubbies (no bypass); but they are $7 for two ($14 to fill one tray in an XP3). So I agree, the scrubbies would fill more canister space for the buck.

 

[Dr Joe]

Dr. Joe,
What environment do you put those in to create anaerobic bacteria? You need a very low oxygen environment to produce facultative anaerobes. Maybe if you buried them under a sand substrate....

Might be an interesting experiment to place a sponge-foam mat on the bottom of a tank and cover it with a few inches of sand. The sponge may offer more low-oxygen surface area than sand alone; especially if the anaerobic bacteria starts foaming right at the transition line between sand and sponge.

You are corect in your accessment of the environment needed but you are assuming the only way to get that is with sand...and let me made it a little more exacting, it is a low dissolved oxygen environment...just remove it and your set.

The sand would filter thru the scrubbies so they would now just be buried in the sand.

I have 3 different de-nitrators, single & multiple chamber units I'm testing for clients at the moment...all functioning well and none have sand in them . (I do have one 10 footer with sand also).

I've made other posts here about these things so I won't take up more space now with it again.

The sponge under sand idea doesn't work because you need a constant water flow or the toxics build up and fish die and everything smells bad .

(And if we vary the idea any more we end up with a UGF ).

De-nitrators are best used in S/W tanks or where water is at a premium and must be re-cycled.

Nitrates are best removed by water changes.

Dr Joe

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