5-Gallon Acropora System

[East1]

I'm going to start documenting a new small nano tank in this thread, 

I want to look at aquascaping this time round, so I'll start with some inspiration 

 

 

 

 

 

[East1]

[Pjanssen]

3 hours ago, East1 said:

I'm going to start documenting a new small nano tank in this thread, 

I want to look at aquascaping this time round, so I'll start with some inspiration 

 

 

 

 

 

Nice. Australia?

[East1]

12 hours ago, Pjanssen said:

Nice. Australia?

I'm not actually sure, I collected these as part of an hours long youtube dive-video binge. I just really like that acro/sand zone interface at the bottom of the structure a lot 

[East1]

 

With a Prime HD and Freshwater HD, it looks very brown and natural during the day

[fabiocassa74]

amazing aquarium, your tanks and a few others really inspired me to get back to the hobby after more than 20 yrs

[justincasper]

Does the combo of Primes give off a more natural look than when you ran a Radion with all channels at 100%?

[East1]

On 4/8/2021 at 6:46 AM, justincasper said:

Does the combo of Primes give off a more natural look than when you ran a Radion with all channels at 100%?

It's been quite a while since I had the radions, but I think so yeah. I don't run both primes at 100, I have all the blues at 100% all day, then perhaps 20% warm white and 15% cool white (there are more overall cool white LEDS compared to warm so this is a balanced intensity)

 

The result is that it looks like a really deep, defined sunlight, while still giving good coral colouraton, I think the warm white gives a whole new dimension to it 

[East1]

 

A view through 3.5 gallons

[East1]

 

5 days worth of Alk testing and minor (>10%) dosing adjustments to stabilise the midday reading

[East1]

It seems there's a really strong relationship between Carbon as CaCO3, Carbon as organic carbon (Vodka, ZEOStart etc) and Phosphate/Nitrate. 

 

The Co:Ci relationship seems to influence coral and ecosystem health as a vector, so if you are adding more inorganic C to organic C, in the case of dosing 2 part and vodka, you have a stable pH and a reduction of nutrient. The amount of Organic C to inorganic C influences P:N. So if you're adding Co and Ci, you need to be adding N and P somehow and neglecting to do this will influence the corals.

 

The amount of P and N influences a number of things, I'll list them in order of severity, least severe first - this relates mostly to Acropora beacuse they display symptoms and can be affected in a matter of minutes in some cases:

1. Coral colouration
2. Coral Polyp extension 
3. Growth
4. Metabolic collapse - this one is EXTREMELY dangerous, being in a ratio of higher N:P and very low to zero levels for both results in pale corals, basal tissue recession and eventually the coral will look 'dry'. Also you'll notice the polyps don't show and almost dissappear, they literally shrink at the lowest levels of P where the coral will consume it's reserves of phosphate and start to shut down. When it's 'dry' or receeding and polyps don't show, adding PO4 with or without a facilitator (especially KZ Flatworm Stop and Coral Booster) will reverse the 'dryness' and polyp extension visibly in moments, when I figured this out within 20 minutes the coral looked different and within a day it started to regain depth to colour. Polyps went from non existent to showing. 

Dosing PO4 using the above, after a day I saw a new host of colours on my corals too. I have cyano and I think the cyano locking up available PO4 was starving out the corals, coincidentally I recall a number of tanks with unhealthy coral and cyano so I wonder if this is regular. Increasing the ratio of Organic C to inorganic C also makes this worse - aka, vodka dosing will increase cyano which further skews the N:P balance. In this state, adding amino acids and organic nitrogen makes it far worse too. 

 

so it seems there's a runway effect, between Co and Ci, and N:P. I recall Triton talking about this with thier STN X product too which fortifies my theory a bit. It seems imbalance of C imbalances N and P, and this is directly shown by coral - hence the age old 'burnt tips' with low nitrate and high Kh, what this actually means is that the ratio of Co:Ci : N:P is off, and it causes metabolic imbalance and that 'dry' tip look. 

 

the most interesting thing of all of this is that while my P was so low, only one coral showed signs and the others looked fine, that coral was also most susceptible to temperature swings. I theorise that the corals kept in these imbalanced conditions can compensate with their internal biology to a point, - STN and after that point it is total shutdown and death - RTN. It's important to be able to recognise the markers for these conditions because I expected a tank would show symptoms across the coral population. 

 

This compounded balance point seems to have a far stronger impact than anything related to trace element imbalances I've experienced so far. 

[mitten_reef]

3 hours ago, East1 said:

It's important to be able to recognise the markers for these conditions because I expected a tank would show symptoms across the coral population. 

one reason that visual observations and "knowing your corals" are very important.  Just want to add to this statement, not all corals would exhibit symptoms at the same stress point, even within the same genus ie. different acroporas have diff tolerance.   after a while, you'll know which is your tank's "canary"  

[East1]

still some cyano 😅

 

[East1]

[East1]

[East1]

6 hours ago, East1 said:

IMO the biggest issue with moving a tank is sandbed stability - even if you use a fresh aragonite sandbed and existing rock with a cup to seed the sandbed, there are some chemical processes that need to bottom out for stability - including po4 adsorbtion to the aragonite, which in itself gives a substrate for diatoms > hair algae > cyanobacteria due to the po4 local concentration. 

 

This then causes algal blooms that can outcomplete corals for nutrients, especially po4, which is a huge risk factor because po4 starvation will cause STN/RTN in acropora and I expect similar stresses in other corals. 

 

To that end, I'd recommend cycling the new tank with existing tank water and establishing a biological base in the sand bed if you're keeping it before moving corals. If you had no sand and just liverock, then moving to a new tank is far simpler because most of the processes don't change at all from an ecological / chemical point of view 

3 hours ago, East1 said:

I've not done much experimentation in this vein, but with my most recent tank I started with 99% synthetic ceramic rock, and fresh sand ( a mix of aragonite and some cheap crushed coral). In the beginning I did dose some PO4 but didn't test as in this stage I expect it wouldn't show on a test kit. I kept dosing alongside some nitrate in a 3:1 ratio till I saw signs of algae growth and then stopped. My thesis was that at this point there was adequate adsorbed phosphate on the Caco3 structure of the sand and synthetic rock that the system was saturated.

 

From this point I got some hair algae that turned into a huge bloom, followed by dieoff and replacement by cyano which also bloomed very strongly and slowed subsequently. During the hair algae stage I noted that the corals were fine and the tank processed nutrient as normal, however during the cyano stage the acros showed heavy phosphate starvation signs - poor PE and a thinning to their flesh. Dosing PO4 combined with Zeo FlatwormStop and Coral Booster reversed this within minutes. FWS and CB are vectors that the corals seem to take up very well and also bind to other elements somehow, as I've used them as a vector for trace elements too. Based on this quick recovery I theorised that the hair algae used what it could, before being out-competed by the cyano able to uptake directly from the adsorbed PO4 on the rock and sand which were locking up PO4 from the corals. 

 

since dosing nitrate and phosphate daily (I'd estimate 0.02-0.05ppm PO4 a day, and about 2-5ppm Nitrate daily) the cyano has eased off and I've seen an increase in coralline growth and also coral growth in the past 2-4 weeks. =

 

I got a bit convoluted but I think it's important to know the full opicture here - you're essentially trying to fill any phosphate reservoirs, to establish cyano and effectively determine the low point of PO4 in the tank, at this point you can add PO4 and it'll be consumed within biological processes fuelled by carbon and skimmed out or consumed by corals. 

 

Mathematically I guess you're derivating the lowpoint of phosphate as a usable element in whatever form it can sequester in the reservoirs of a tank, with the sand being a big component. Going through this process navigates through the most dangerous phas of biostability that would affect sensitive corals and allows you to then create a proper mode of phosphate cycling and removal via biology as opposed to via PO4 removers.

 

I would further theorise that's why you see some people with rock that grows awful algae in certain spots, and why some people will have high phosphates for extended periods - you can't just remove it from the water because the water is simply a buffer zone between the biological reservoirs of Po4 and the physical chemical reservoirs of Po4, and balancing this is important for long term stability. 

 

 

 

Just crossposting this from another thread so I can save my thoughts. 

 

Here's a photo of the tank and the sump

 

[East1]

Couldn't figure out why some of my corals looked unwell, it was similar to phosphate starvation but I've been dosing po4 religiously, so I took them out to inspect and found a corallivorus snail had munched the base of one, and also what I thought was a couple AEFW,

 

Took the affected corals to a Melafix dip for 4 minutes and I think I must have found 20-30 soybean sized worms on them, nothing small just the larger ones. I was surprised as I use Flatworm Stop regularly but it seems that disrupts the ability for the young to attach and start growng, but doesn't kill the larger worms. Their size must have been stressing out the colonies and starvation from overconsumption I guess must have similar symptons to nutrient deficiency. 

 

The corals look a little worse for wear, lots of basal recession that's stopped in a day now, so I'm eager to see how we progress. 

[East1]

Everything seems to be growing back in well, I upgraded the lights and have started experimenting with microelements to determine which elements relate to quick coral death and which are responsible for healthy growth, to classify a set of absolutely essential elements for surivival and further for colour / growth.

 

You can see below where the AEFW really took hold in teh tank, relating to DKH spikes. It's pretty obvious now things are back on track at my usual dosing amount. 

 

[East1]

one of the things I don't discuss is flow, but my tank has a weird flow pattern. about 6 hours of the day the tank has 0 flow, otehr than the return pump at 10gph. The water is totally stagnant which makes for amazing top down views, but it also serves a purpose,

 

the reasoning is that it's actually only for 30 seconds at a time, and I think it's important for the water in an SPS tank to have moments where it has 0 velocity, and moments where it has relatively speaking, 100% velocity. I do this by having a pump pulse at intervals, with a second pump creating a standing wave on top of that, and I stagger the two, so I have moments of standing wave + interval flow, and moments of 0 standing wave or interval flow, and everything in between. This constant change means that there are functionally no dead spots for flow from a tissue health /boundary layer perspective and I think without that, this tank wouldn't be nearly as healthy 

[DevilDuck]

This is great information and your tank looks fantastic!

 

[East1]

\

Changed up the lighting to a single Hydra, and fragged down the acropora valida that had the most flatworms to get all the eggs out. Hopefully should be the end of those! 

 

Also did the first nitrate and phosphate test on this tank, 2.5ppm Nitrate and 0.0ppm phosphate on the salifert test. gonna start upping phosphate dosing this week coming 

[East1]

On 6/14/2021 at 7:17 PM, DevilDuck said:

This is great information and your tank looks fantastic!

 

thank you! 

 

the difficult part is remembering it all, after writing the post about how important phosphate was in April, I was struggling to figure out why despite dosing phosphate my acros were looking bad, and only when I came to post a photo did I realise that my own past-advice was useful.

 

shockingly, I dose about 0.1ml of Easylife Fosfo a day, and despite that I've got an acro showing phosphate starvation and 0 measurable po4. It's really been eye opening keeping such a density of acropora to see what elements they consume at what rates. 

[East1]

This paper blew my mind:

 

Changes in Radial Polyp Tissues of Acropora Longicyathus After Long-Term Exposure to Experimentally Elevated Nutrient Concentrations

Daniel J. Bucher and Peter L. Harrison

Firstly, I made my text blue to differentiate between the authors and my musing.

 

In essence, the researchers selected areas of reef to act as nitrogen- and phosphate- boosted tests against a control, and a null variable where both nitrogen and phosphate are elevated relative to their startpoints.

 

It starts by defining coral stress response, similar to that 'dry' look I've seen described before. 

 

 

and then, the general structure of the coral:

 

 

but interestingly, defines the entire colony in relation to the axial polyp, as this extends all the way down the coral, and seems to be fed from the excess of the radial, or hetereotropic, tissues. This explains a lot about the growth of corals when they arrive, particularly frags - they base out and produce polyps and then start growing from the tip. 

 

Elevated nitrogen results in Phosphate Starvation? I'd seen this alludeed to before, by Hans Werner Balling on r2r, he goes in depth about using Urea to feed his tank nitrogen instead of KNO3, and how indirectly that staved off cyano. (this is the same guy that made the Balling method of supplementation, this whole thread is worth a read.

 

 

 

This basically shows that the amount of skeleton, relative to that of polyp can vary, as per this diagram.

 

 

and that the growth of coral tissue is a function of it's limiting nutrient - we know this as Liebig's law of minimums. This coincides with a similar post I found on reef2reef: 

 

 

this indicates that this dude's coral was limited by strontium, and increasing that limiting factor with all other stability factors equal, he saw a change in the _type_ of growth - something that always interested me when looking at 'old tank syndrome' tanks. 

 

What was interesting to me was to confirm another observatiion, that in some conditions a coral will not produce slime:

 

 

But, to refer to another longstanding forum myth, the _redfield ratio_, we see that the actual ratio of these nutrients is far more important. 

 

 

Anyway I've kinda rambled, the gist of it is that it seems the major elements: Nitrogen, Phosphour, and their ratio in the water can affect the tissue to skeletal density of acropora, and further this implies that it's whole trophic strategy is then reliant on the ratio provided, ie. If we have high phosphate in the water, the coral isn't adapted to slough off sediment, and perhaps it implies the trophic direction of the coral is geared toward taking in ambient nutrients from the water and light, vs when nitrogen dominates, the coral expects murky, food-rich waters and diverts resources accordingly.

 

This then might imply that for as long as the above ratio is correct, then the limiting elements of this list: Potassium, Carbon, Boron, Bromine, Flourine, Iodine, Iron and Strontium will define the growth rate, and ultimately the overall structure and shape of the colonies grown. 

 

for the first time, in my mind, I think I have a formulaic approach to creating an environment that can continously grow acropora, prior to this the only hard 'rule' I had known was to keep alkalinity stable, but I think alkalinity is only one factor in the above list, because technically it's just 'Carbon'. 

 

 

[East1]

[Jaren45]

I absolutely love this thread, even if I don't understand it 100% thanks for all the knowledge!