This is starting to become comical
@ScubaSkeets …ya know I’ve labeled you a troublemaker; you started this thread ( can’t believe I waded through most of this thread lol)
An excellent way to increase the comparative advantage!
I would live to see pics of both!
I was simply sharing my attempts to try in the world of scrubbers. Nowhere did I say that they just don't work, if you read back to my thread I simply said I will stick to my refugium.
Delusional thoughts from fantasy island
Get ready for excitement! I'll demonstrate the power of a good model!
To alleviate confusion around this, I decided to model the effect of a refugium/ATS and prove that growing algae in one location will have an effect on the amount of algae grown at a different location (and even has the ability to make it go to 0).
Consider the following setup of a display tank and a refugium/ATS with volumes of V0 and V1, respectively.
The Nutrients (N) in the tank are considered "well mixed", which means that the concentration is instantaneously equilibrated, and local effects are not considered, i.e. algae in the display has access to the identical nutrients in the refugium/ATS and vice versa. p0 and p1 are intrinsic rates of nutrient intake per unit volume for the display tank algae and fuge/ATS algae, respectively (these values are different because of lighting power/spectrum differences, etc. but could also be more general to measure of other factors too).
With this setup, we can model a set of differential equations that describes the change in nutrients in the water column, as well as nutrients that accumulate in algae from the display tank or fuge/ATS.
Here, N(t) is the amount of nutrients in the water column, A0 is the amount of algae in the display, and A1 is the amount of algae in the refugium (both A0 and A1 are in units of nutrients). We can also model a constant influx of nutrients to the tank (i.e. through feeding). In this model, I assume no outflow of nutrients, so the sum of N, A0, and A1 is always increasing by c*t.
Solving these differential equations for N, A0, and A1 yields the following:
Now the neat thing about this is that the growth of algae in the display is proportional to the ratio of intrinsic growth of the display and its volume by the total algal growth (p0V0 / (p0V0 + p1V1)). If we take this to the limits and have a significantly larger Fuge/ATS than the display tank, we can see the algae growth in the display tank goes to zero!
This is a proof that your model is wrong! Algae grown in one side of the tank *DOES* influence algae grown at another, and a sufficiently large fuge/ATS *CAN* completely outcompete algae in the display.
So, finishing our discussion: if a fuge/ATS doesn't work, it's NOT because algae grown at one location can't compete with another location.
Backing up though, how many of us have a fuge/ATS that's larger than our tank?? I doubt many! So what might these curves look like in practice? Well, I computed the nutrient/algae growth as a function of time from the above derivations and there's some informative data!
First, imagine we have a fuge the same size at the display, with identical lighting power/spectrum. Both A0 and A1 curves are the same (green and red respectively, though green is completely overlapped by red in this plot; free nutrients as black curve) and the ratio of algae in the display and in the fuge is 1 (seems reasonable!). BTW, code is in python and available on request!
Next, convincing ourselves that it's possible for a mega sized fuge (100x the display with a comparative advantage of 10x!) to completely out compete the display tank. A0/A1 ratio is 0.001(this value actually just ends up being the ratio of (P0V0)/(P1V1) so I'm dropping it from subsequent plots.
Okay, I know you're saying this isn't realistic! So what about a fuge that's half the size of the display (still a big fuge) with lights that give a 10x advantage (this is a guess but we can throw this parameter around). Doesn't look too bad! definitely helps, but this model predicts significant algae still growing in the display (green curve).
What about a significantly smaller ATS (5% of tank volume) with bigger advantages (50x comparative advantage to display)? Similar split.
What if we have an underpowered fuge/ATS? lets say same size as above but only a 10x advantage to the display?
Now the algae in the display starts to win! Though its important to notice that the display algae is still much lower than it would be without the fuge/ATS.
Now, I wouldn't read into exact values (a little arbitrary), but this shows how we can tune the knobs of our system and how it will influence the tank!
Summarizing the whole discussion, this model is actually *consistent* with a lot of what you say and actually serves to validate your experience. It's clear that in some circumstances, an ATS and fuge is not "all you need" (though to be fair I'm not sure anyone has actually ever said that in this thread lol).
It is consistent that even with an ATS, you and others can still see algae in your display tanks. However, it is clear that an ATS can work, but might need to be supplemented with some other practices that add to the comparative advantage, like... herbivores!
The big difference, and the reason I've been persistent is that your explanation of "why" just didn't hold water (pun intended lol).
I hope you have a great Tuesday!
I’ll have a go, lol. This documents that algal growth rates are nearly maxed out at natural seawater levels, presumably undetectable by us with our test kits. So lowering them but remaining still detectable would have no effect; if folks look hard enough they will probably find research that states the opposite;
academic.oup.com
Lol. Ford circled their problem in the center of their grille. At least jeep gives you a nice seat(the front bumper) to sit while you wait for the tow truck
I maintain 5ppm no3 and .02 po4 with carbon dosing on a doser… I spend 60 seconds every 4 months filling my doser container with bacto balance lol..
You have NO idea what you're talking about! Ford trucks don't even work!
