New Year, New Scape...

[Geoffrey Rea]

Bacteria. Or colony size of the plethora of autotrophic and heterotrophic bacteria’s found in an aquarium is the short answer. But I’m not claiming a simple causative relationship between Co2 and stocking levels. Just that a range of available o2 in an aquarium is a reasonable gauge of what you can do with that system. System design based on its lowest and highest measures in a 24 hour cycle.

 

[Geoffrey Rea]

Your question is complex because we’re talking about a dynamic system. In this specific aquarium there are two air stones that run from lights out until ten minutes before the Co2 kicks in. This is a safeguard. O2 levels should not be consistently below atmospheric levels at any point as a good goal. Yes this gasses off the high saturation of o2 at the end of the photo period in a high tech system but it (in theory) guarantees a level of o2 that keeps the system running should the worst happen e.g. a few fish die and place a demand on o2 at night.

The plants are done for the day, they’re pearling because they’re full of o2 and the water is saturated too - hence the bubbles. During the day the whole surface has ‘good’ agitation as I see Co2 as a consumable and if the plants are pearling Co2 has done its job. Plenty of o2 for all.

If I was running low tech I would aim for large amounts of surface agitation to maintain atmospheric levels through gas exchange 24/7 e.g. overflow unit that also skims and sump wet dry/trickle tower to keep primary gas exchange outside of the display tank rather than canister filter based in a 400l planted tank. This doesn’t even begin to address nutrient distribution or light or in tank flow or the relationship between temperature and saturation of gases into water....


But with relevance to your questions:

Interested why less stocking would mean less co2 for you? Would also be interested to hear your different strategies? Just curious!

The stocking level of plants, fish, invertebrates and demand on bacteria to process organics/inorganics are all dependant on o2. Artificial levels of Co2 lead to artificial levels of o2 in high tech. Low tech demands you base this stock list on what the system can do at an optimal of atmospheric levels. Have seen beautiful low tech tanks run for over a decade because they were designed with this in mind.


Just my two cents on the topic @Matt @ ScapeEasy

Not very succinct but got two kids jumping all over me like a human trampoline and fixing a dyson whilst writing this

 

[Jayefc1]

That was a good read very interesting
Who says men cant multi task
Fixing the hover entertaining the kids and sharing good knowledge sounds like a true millennial man to me
Cheers
Jay

 

[Geoffrey Rea]

I failed at fixing the hoover though @Jayefc1 Suspect the mechanism that selects between the actual hoover and wand is bust so it’s always hoovering (poorly) from both. Serviced the whole thing and still it persists

Did succeed at replying though and made a fabulous trampoline for the kids. Two outta three ain’t bad for an evening.

The Dyson mystery continues...

 

[Jayefc1]

Have you washed all the filter outs it is

The Dyson mystery continues

Have you washed all the filter outs it is APITA when our filters glog just a suggestion I'm guessing a man of your calibre has tried that though
Cheers jay

 

[Geoffrey Rea]

Got a Dyson Cinetic Big Ball, doesn’t have filters. Unsure if that’s a good design or not currently but evidence says not so far.

Not tried to diagnose any further than before but when you remove the cylinder containing the cyclone tech and bin the problem stops.

 

[Matt @ ScapeEasy]

Interesting topic this... my view was that more bacteria and fish meant more respiration and therefore more co2... am I barking up the wrong tree?

 

[Geoffrey Rea]

Depends.

my view was that more bacteria and fish meant more respiration and therefore more co2... am I barking up the wrong tree?

When you step towards specifics rather than principles the knowledge can quickly take you away from usable, executable solutions. Not to throw the baby out with the bath water.

Yes livestock will produce a byproduct of Co2. How much? They also produce waste that uses up oxygen when being processed by bacteria. Is it usable in the relationship of Co2 to oxygen through photosynthesis by plants, is it consistent?


What relationship do you see between water temperature, pH, oxygen, nutrition and toxins for ‘bacteria’? More of what specific groups of bacteria? What is their rate of division? Even cleaning your filter sponge of decaying organics will cause die off of large amounts of the heterotrophic bacteria that were dependant on organics to maintain their colony. This die off then uses up more oxygen. Is there enough to cope or has your water gone cloudy?


I’m stepping off the track of solely using biological means of getting oxygen (as a product of photosynthesis in low tech) into water and championing the idea that using gas exchange is a more stable and reliable means of achieving this. It’s consistent and isn’t as dependant on so many variables.


What is of relevance here is the scale of the answer you’re looking for. If it’s restricted to the amount of Co2 produced biologically then fine. If it’s in how the amount of Co2 relates to oxygen saturation in water through biological means in the system then cool. If it’s about how to achieve a balance in an aquarium system so it’s relatively stable over a 24 hour period so everything is dependant on a key variable of oxygen, then we’re at a system level of thinking.

A separate arc to this is gas exchange is not exclusive to oxygen obviously, it also leads to consistent levels of Co2 based on atmospheric levels. But Co2 is important during the photo period, oxygen gets no rest. It’s required 24/7.

High tech systems are a different animal yet again that require a different design to low tech. An obvious statement but these days I think less in terms of ‘high tech versus low tech’ and more in terms of how hard you’re pushing that accelerator peddle down, and also what does this affect within the limitations of the aquarium system?

 

[dw1305]

Hi all,

Unsure if that’s a good design or not currently but evidence says not so far.

There used to be a special repository for Dyson "Hoovers" at Carymoor (Dimmer Landfill). I asked whether that was because they were worth repairing and they said no, they were all for stripping and then landfill, they just got so many of them in every week that they wouldn't fit in a normal skip.

O2 levels should not be consistently below atmospheric levels at any point as a good goal. Yes this gasses off the high saturation of o2 at the end of the photo period in a high tech system

A separate arc to this is gas exchange is not exclusive to oxygen obviously, it also leads to consistent levels of Co2 based on atmospheric levels. But Co2 is important during the photo period, oxygen gets no rest. It’s required 24/7.

High tech systems are a different animal yet again that require a different design to low tech. An obvious statement but these days I think less in terms of ‘high tech versus low tech’ and more in terms of how hard you’re pushing that accelerator peddle down, and also what does this affect within the limitations of the aquarium system?

@Geoffrey Rea that is a great post, and I really like the "peddle down" analogy.

Another reason for having a large gas exchange surface is that plants store a lot of the CO2 and oxygen (from respiration and photosynthesis) internally in <"lacunae and aerenchyma">.

There is some discussion of this in <"Does surface agitation....."> and links.

cheers Darrel

 

[Geoffrey Rea]

Thanks for the links Darrel. A more complete picture of what’s involved.

As for the Dyson... Not ready to give up yet but need time to investigate. About 5 years ago Dyson seemed to change designs for the worse. Find it offensive to throw away a hoover after just three years due to poor design/materials or both, but we will see if it is destined for landfill soon enough. Hope not.

 

[dw1305]

Hi all,

Thanks for the links Darrel. A more complete picture of what’s involved.

I spend a lot of time on <"other forums"> trying to tell people how important oxygen and plants are, it has to be said with varying success.

my view was that more bacteria and fish meant more respiration and therefore more co2..

It does, more CO2 and less oxygen. It is back to @Geoffrey Rea's

more in terms of how hard you’re pushing that accelerator peddle down,

You can design systems to deal with a high bioload (a lot of "accelerator pedal" for that component), by maximising oxygen input, increasing the gas exchange surface area and adding in plants (ideally with the aerial advantage).

Scientists use the Biochemical Oxygen Demand (BOD) concept to quantify how polluted an river, or effluent, is. You can design systems that allow <"nitrification of raw sewage etc."> even though the BOD value of raw sewage is ~600 mg/L of oxygen and water can only hold a maximum of about 20 mg/L of oxygen.

cheers Darrel

 

[Geoffrey Rea]

When you open the filter up you can tell a lot about the oxygen levels in the filter by the nature of the biofilm. If it mainly consists of a lot of fine black particles these are the (largely carbon) remnants left when the microbial "low hanging fruit" (short chain carbohydrates, proteins etc.) have been consumed ("oxidised").

This is the situation when the microbial activity has been aerobic and the filter media hasn't been oxygen depleted.

This complete oxidation process is used in waste-water treatment, it is the "extended aeration system".

Interesting reading. I only use coarse prefilter sponges in canister filters these days for high flow of oxygenated water to the media. Not really considered what form the end product of oxidised carbohydrate and proteins would look like but grains of carbon obviously makes sense.

 

[dw1305]

Hi all,

I only use coarse prefilter sponges in canister filters these days for high flow of oxygenated water to the media.

That is it really. It isn't the biological media that matters it is is the dissolved oxygen.

It is why all the discussion of the relative merits of Biohome, Siporax, Matrix etc in terms of pore space, denitrification etc. is <"just froth">. Dissolved oxygen is the coffee, and in oxygen terms <"plants are the gift that keeps giving">.

If any-one wants to wade through it the <"Using deep gravel....."> thread on PlanetCatfish gives a lot of back-ground and some scientific papers, I've linked in the last page, but the whole thread is worth a read (if you have time).

Not really considered what form the end product of oxidised carbohydrate and proteins would look like but grains of carbon obviously makes sense.

If you look at the faeces that shrimps (or woodlice) produce they are long lasting and fairly inert for exactly the same reasons, the animal (really its microbial symbionts) has processed a lot of low value food to extract any goodness, and any nutrients left are practically unavailable.

I've corresponded a little bit with some of the scientists who have worked on the gut flora of Panaque spp. These are xylophagous "wood eating" Loricariids with highly evolved dentition, but apparently relatively unspecialised gut morphology.

I was initially interested in them because they were a fish often involved in "unexplained death" (for experienced aquarists), and after a while I began to strongly suspect that this was an oxygen effect and that it was caused largely by people using their external filters as syphons for all the cr*p and saw-dust they produce. It doesn't have a high bioload, but it does easily clog the filter.

It is another long thread (on PC) but if any-one is interested <"Nitrogen fixing......" >

cheers Darrel

 

[Geoffrey Rea]

Hmmm....

Someone has been eating my Buce

 

[Jayefc1]

Not me

 

[Geoffrey Rea]

Just shy of five months:

All much of a muchness from here on out. The only real improvement will be on the left side where the bolbitis will be cut back to temporarily retrieve some light to the substrate level. Also root tabs will be selectively buried to pump up the crypts at the base on the left to diversify textures and shades. Beyond this... just the propagated moss to be removed for the next scape.

Planning out a sumped high Co2, light, o2 and filtration Aquascaper 600 so attention will now be diverted to the next project.

Thank you to those that have followed along for the journey and commented along the way

 

[Geoffrey Rea]

PS completely forgot to mention solved the Dyson mystery...

Bit of manzanita stuck right up in there

Hidden really well and barely noticeable without a torch. Was preventing the selection between hoover and wand.

Another mystery solved and faith in Dyson restored.

 

[Geoffrey Rea]

Update. Coming up to eight months:

Finally got around to giving a huge haircut to the bolbitis. Filled a ten litre bucket with leaves pressed down. The bleheri and vallis nana are gone as they’ve done their job of adding plant mass to get things up and running, but are no longer needed. Also decided to keep the fissidens and tied some down the other day, rather than letting it grow in clusters. It grows really well in this setup and is squeaky clean so it would be a shame to lose it all. Even got some emergent growth at the back left corner from the Proserpinaca palustris. Training it up a bit of manzanita poking out of the water to see what comes of it. If I’m being totally honest, I forgot it was in there The overall trim back has given the crypts a chance to catch up along the base:

Should help to add some interest to the side views, although this scape was only ever meant to be viewed from the front in its location.

Was budgeting a slow burn twelve months to get to something akin to a ‘finished look’ but will probably hit that in a couple of months time at this rate.

It was never intended to be anything other than an easy to maintain setup. So far it’s proven to be the easiest scape I’ve ever personally attended to thanks to huge volumes of plant mass. Less than an hour per week on average to maintain and these days the glass doesn’t even need cleaning. Hoping this continues as this little monster is the polar opposite and it isn’t even planted up yet:

This AS600 setup has eaten up more than a few nights sleep but glad to say the sump design has worked out a treat and plumbing is watertight. Planting up tonight, happy days

 

[Tim Harrison]

Looking great

 

[Geoffrey Rea]

Thanks @Tim Harrison