Update from a great thread on substrates...2004

[BSBARTON]

I read the below thread on substrates and sediment removal. I am in the process of setting up a 145g and would like to incorporate this design.

Did anyone set this system up?
How has it worked for you?

The concept was thouroghly discussed and a trial was make. But no feed back as to the long term cloging or other positive/negitive side effects has been posted.

http://www.reeffrontiers.com/forums/showthread.php?t=5476

 

[MikeS]

Yeah, that was a good thread...aside from the mock-up that mojo Mike made, I don't think anybody has tried that...a few here have mentioned wasting plenums, but I'm not sure if anybody has actually followed through...

I was planning on it, but a divorce and rapid relocation of my tank de-railed my plans...I now have an empty 75 gallon, and all the acrylic to make the plenum, in addition to the dried live rock for substrate, but I don't know if I'm going to do it or not...have not made up my mind...

MikeS

 

[BSBARTON]

Mike,

Sorry about the Divorce. I went through one and it wiped me out. If it wasn't over you could file a motion for tank support, FOT (friend of the tank)..lol. Give it some time...

Anyway back on topic. I am going to try it. My tank is 145G, 18 x 72 footprint. I think 4 zones would work nice for the flow. 18 inches each. With a 1" rise that is about a 6 degree angle for the baffling. The bigger angle will mean less force required to get the accululated waste moving. Another thing I am considering is to cut a couple of holes in the base top. This would allow a site line to monitor the long term settling and success of the concept.

The next mod I am considering is to split the tank into half. Meaning that time of removing the build up I only affect half the tank at a time. Then alternate the removal by a week or so. This would minimize the the oxygen effect everyone antisipated.

Thoughts?

 

[MikeS]

Mike,

Sorry about the Divorce. I went through one and it wiped me out. If it wasn't over you could file a motion for tank support, FOT (friend of the tank)..lol. Give it some time...

Not a problem, this happened well over a year ago, and the plus side to it was that in the rush to move the tank, I opted to try a bare-bottom setup...been running a BB tank for 14 months now, after a DSB for 5 years, I get to see first hand the pro's and con's to that approach as well...I have the larger tank, I just haven't decided what to do with it. I won't likely move the contents of my tank until spring or summer into it, so still have some time to decide what to do...

Anyway back on topic. I am going to try it. My tank is 145G, 18 x 72 footprint. I think 4 zones would work nice for the flow. 18 inches each. With a 1" rise that is about a 6 degree angle for the baffling. The bigger angle will mean less force required to get the accululated waste moving. Another thing I am considering is to cut a couple of holes in the base top. This would allow a site line to monitor the long term settling and success of the concept.

Well, as I saw it, the goal was to allow as little solid waste into the plenum as possible in the first place. I always viewed it as a method to be able to remove accumulated by-products from the depths of the substrate more than anything, effectively re-newing the substrate so to speak, and that's why I always opted for a finer substrate size than some of the others did...I'd say a good 2-4mm substrate with lots of flow to keep solids from entering the substrate in the first place would be the way to go.

The next mod I am considering is to split the tank into half. Meaning that time of removing the build up I only affect half the tank at a time. Then alternate the removal by a week or so. This would minimize the the oxygen effect everyone antisipated.

Thoughts?

Not sure on that one. A tank divided in half like that, you'd be impacting the half being drawn against just as if it was a seperate tank...it would be like trying to run two tanks at once...I'd say leave it as a whole. The frequencey and amount at which you draw off the plenum would be the important thing here...I'd opt for only once or twice a year, and no more than 20% of the tank volume of water being drawn off at any given time...

MikeS

 

[buffalo]

The part i did not understand was the debri in the pleum zone. I ran a plenum for 6 years and the plenum stayed clean , just some fine sand made it there. I do like the idea of being able to pull water from that zone occasionally 6month to a year.
I was wondering if having crush coral as the layer on of the plenum and then sugar size sand on top of that seperated by window screen would work.
This will all be crazy to those who think the plenum don't work and those who think the DSB is a ticking time bomb.

 

[BSBARTON]

I just set up a 70g with a plenum. 1" pvc arond the perimiter and a 5 mid suports. Toped that with egg create and window screen. added 2" of crushed coral and some sand then another window screen. topped it off with more crushed coral.

This is a copy of the G.A.R.F. plenum. They have had tanks set up for many years without problems.

 

[morgan]

um i think this is relevent
there was a post for 230gl lps display the member was from indo i think he had a plenum installed although his power heads similar to mj had long tubeing that went in to the plenum drawing water through the sand bed and pushing it out over the tank this looked like a good idea to me and would pretty much move that water out with out u having to sphion the very bottom

 

[aquariumdebacle]

I prodded Mike into discussing these designs on a trip to Spokane a few years back. What came out of the argument (I mean discussion) was that the subrstate is not a godd nutrient removal tool and infact becomes a nutrient sink where nutrients build up to the point of being released back into the water column. We attempted to look at ways that would prevent or at least slow the accumualtion of nutrients in the substrate.

I am currently working on a design for a DSB with a plenum. I don't think I will have a viable testing experiment as I have included way too many variables. I have another post on here asking for help in the design.

http://www.reeffrontiers.com/forums/showthread.php?t=21048