Trying something new - Walstad method and NPS filter feeder tank

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I wasn't planning to add other types of snails, but I wouldn't want anything that could prey on bivalves! I didn't realize they would do that.
 

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What I've read is that while most macroalgaes don't use holdfasts for much, many of the rooted siphonaceous species (caulerpa, halimeda, udotea, penicillus, etc) do use them for a significant part of their nutrient uptake. Here's a study I found about Caulerpa prolifera doing this - https://pubmed.ncbi.nlm.nih.gov/32175590/
I read the abstract which did reinforce there is significant nutrient uptake thru holdfast. I find it interesting, that nitrate was the molecule absorbed in substrate and not ammonia. Unfortunately, the link was the “abstract only” as I searched for details on how experiment was conducted.
 
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“Good luck with your experiment and keep on thinking outside the box - inside the box will always result in stagnation!“


@Lasse

“Inside the box will always result in stagnation” , I definitely like. Especially coming from a municipal wastewater scientist who got paid to stir it up! This one rates as high as Niels Bohr definition of
Expert: Someone who has made every conceivable error in a field of endeavor.

Lest us continue to develop interest in “holistic reefing” forum.
A Cajun Aggie in Austin &
A “laissez faire” reefer
 

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Add me to this list

My refugium is something like this - but I did not incorporate soil in my mix of the DSB in my refugium. However I have reverse flow through the sand bed of around 300 L/hour and I injected skimmate in the plenum below the sand bed when I started up. I inject around 24 ml 8% ethanol in the plenum every day. For the moment I add a water flow for 30 minutes each hour and if my redox is above 0 - I add ethanol. In this way I alter between aerob and anaerob environment. With other words - between reduction and oxidation.

See below ORP lower than 0 = reduction - higher than 0 = oxidation

1767881140890.png



My aquarium is a heavy loaded 300 L system and I can control my NO3 concentrations this way. I control - for the moment - my PO4 through GFO. My GFO reactor have an apartment with filter floss before the GFO in order to keep organic matter (and hence bacteria growth) away from the GFO. I have a skimmer. There is a lot of no photosynthesising but filtrating animals in my tank, sponges, yellow sun coral, small feather dusters (at places there my copper band can´t reach them) - even tunicates grow in some places. There are sediments ending up in some places - and I never clean it up. There is tones of cryptic zones in the display. I do not have Zostera (eelgrass) but I know one place there my friends have succeeded with this tricky plant in a DSB based system.

The aquarium is nearly 10 years old

If you want to use a bacteria driven system - you should maybe add a skimmer and use the skimmate in order to feed your filtrating organisms - there is no better place for bacteria growth than the skimmer cup! In order to fight one type of cyanobacteria mats I use marine snow (fine CaCO3 powder) that have been soaked in skimmate for half an hour. And my cyanobacteria mats slowly disappear.

Good luck with your experiment and keep on thinking outside the box - inside the box will always result in stagnation!

Sincerely Lasse
Lasse,
Inside the box will always result in stagnation” , I definitely like. Especially coming from a municipal wastewater scientist who got paid to stir it up! This one rates as high as Niels Bohr definition of
Expert: Someone who has made every conceivable error in a field of endeavor.

My friend,
Let us continue to develop interest in “holistic reefing” forum.
A Cajun Aggie in Austin &
A “laissez faire” reefer.
 
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It's been kind of interesting just to watch what the soil does. It's lost a lot of its crumbly/grainy texture and turned into something much more uniform and fine grained, resembling an aquatic sediment. I wonder if that has to do with the original biofilms dying off. Whenever I stir it up it still rapidly settles. It never started to smell bad, just mildly earthy. The live mud and mangrove propagule just shipped this morning so hopefully I can actually start my experiment in a few days.
 
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I just set up the display tank. I tried to make an aquascape that would encourage strong laminar flow with no dead zones and have lots of caves and crevices and shady overhangs to make a good habitat for the fish and inverts I'm planning to get. I used a piece of lace rock along with black lava rock and some stones I collected outside. I know that's not recommended in saltwater and I normally wouldn't but I think once you've put actual topsoil in the tank it's a little too late to worry about what the rocks may or may not be leaching, plus the DOC from the refugium will help to bind any heavy metals and the plants should uptake a lot of them as well. I reused sand that I got from a beach for an old tank that I've since taken down. The water is a bit cloudy right now so I'll have to wait until it clears up to post a picture.
 
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I just realized that this is a terrible experiment :P Way too many variables and way too many things that you'd never do in a normal reef. That's okay though, I'm having fun and I can definitely still learn from it :)
 
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@Subsea I was reading through some of your threads and your method of reefkeeping is very interesting to me. The ecology you describe sometimes reminds me of what I've been reading about in Diana Walstad's book - she uses plants to uptake nutrients and encourage the growth of diverse bacteria in the substrate and mulm and on leaves rather than relying on nitrification. I'm going to try to learn more about the microbial loop you've established.
 

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I read the abstract which did reinforce there is significant nutrient uptake thru holdfast. I find it interesting, that nitrate was the molecule absorbed in substrate and not ammonia. Unfortunately, the link was the “abstract only” as I searched for details on how experiment was conducted.
A young couple who was excited to grab up a bunch of my Dictyota coriacea from my temperate tank last year. They were working on a study of nitrogen transport in marine algae and plants, although now that I think about it, it may have been carbon... Whatever... The point is... wait, I am pointless. 🤔
Your tank excites me, @Paul B's tank excites me, @Lasse tank excites me, This experimental tank excites me. Anyone that does anything beyond the "norm" makes me smile and is interesting to me.
Thinking outside the box is a road of many wrong turns, but it is a road to success.
Still pointless and rambling....
 

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A young couple who was excited to grab up a bunch of my Dictyota coriacea from my temperate tank last year. They were working on a study of nitrogen transport in marine algae and plants, although now that I think about it, it may have been carbon... Whatever... The point is... wait, I am pointless. 🤔
Your tank excites me, @Paul B's tank excites me, @Lasse tank excites me, This experimental tank excites me. Anyone that does anything beyond the "norm" makes me smile and is interesting to me.
Thinking outside the box is a road of many wrong turns, but it is a road to success.
Still pointless and rambling....
A friend with scientific background sent me the rest of the article on Caulerpa Prolifera. Amongst other things, the submerged part of holdfast favored uptake of nitrate to ammonia. Caulerpa Prolifera sequestered both inorganic & organic nitrogen & phosphorus in submerged part of holdfast and that was NEW information to me.

When I worked as a municipal waste water superintendent, we stressed activated sludge with low oxygen to increase net phosphate uptake of bacteria repairing membrane of cell molecules. Go figure.
 
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I should add that I'm cycling it with mulm from another tank + fish food. and I'm doing small daily water changes
 
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I should add that I'm cycling it with mulm from another tank + fish food
Skip the ghost feeding if you start with mulm from another aquarium - get a fish and feed sparely - like my suggestions here

Sincerely Lasse
 
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IMG_0326.jpeg
IMG_0329.jpeg

Here it is. The light I'm using is dim enough that I can't get decent a picture with my phone unless I turn off all the other lights in the room. The water flows in a circle around that big rock sticking out in the middle. I'm gonna add my feather duster and maybe a goby in 2-4 weeks once it's cycled.
 
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Skip the ghost feeding if you start with mulm from another aquarium - get a fish and feed sparely - like my suggestions here

Sincerely Lasse
I appreciate your advice and I know you're very very experienced but I'd rather use the method that I prefer and that I've successfully used on all of my tanks.
 
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I'm adding as many kinds of microfauna as I can from my other tanks. I've learned that I cannot dig faster than a spaghetti worm...
 
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My mud and mangrove got here in the mail today and I set up the refugium. I added about an inch of the soil I've been preparing, a pound of live mud, and then about an inch of oolite. I made a pile of lava rock in the corner for added filtration and habitat and to weigh down a bubbler. I was planning to add a pump but I think the flow from the bubbles is enough. I saw some spaghetti worms in the mud along with a couple others that disappeared before I could tell what they were, and the mangrove is beautiful and healthy and already sprouted. I got both from Addictive Reef Keeping and I'm very happy with them. I moved all the macroalgae from another tank where the inhabitants weren't playing nice with it. I planted Caulerpa mexicana and C. brachypus in the substrate, and I wedged C. lentillifera and Gracilaria hayi into the rocks. I deliberately popped a Valonia "bubble" into the water as well; if it grows out of control that just means it's doing what I need it to do. I might add some other macros and soft corals and such later. I added some mulm from an established tank too. I have a bright grow light on the mangrove and a freshwater plant light on the tank itself. It's all very well lit. I've been enjoying the shimmering effect from the bubbles. I'll post pictures tomorrow :)
 
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I was just putting tin foil on the back and sides of my carnivorous plant terrarium to reflect light back in and it occured to me that I should do the same on the refugium. I also changed out the heater because the old one wasn't working.
 
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The water is golden brown with what I assume is diatoms. They're also growing on the glass, on the macros, in the upper layers of substrate... there's bubbles everywhere. It's actually very pretty. I assume they're feeding on the excess nutrients leaching from the soil. If this works like it does in freshwater then the macroalgae will outcompete it in a matter of time and the soil will be stabilized by bacteria and mangrove roots.
 
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Looks like the pumps in the display tank are generating plenty of heat. So much for keeping it cooler. I'll just let the water circulate through the system like normal instead of trying to keep the two tanks at different temperatures.
 

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