George Farmer said:
Thanks, Tom.
You mention Amano's use of CO2 but from what I've read he rarely runs over 20ppm. This seems to be evidential when we see videos of the tanks in his gallery. For example there are 120cm+ tanks with a single glass diffuser at one end, with most of the bubbles rising straight to the surface, because the circulation is also relatively low (one filter with one set of lily pipes).
I've seen too many aquariums and measured CO2 very very carefully over the years to believe it's 15ppm on every one of those tanks.
I've seen many tanks and each one that looks like those has much higher ppm than that/what has been stated when I measured it myself..........
In other words, I'd have to have some referenced standard and then good methods to be proven wrong and I'd want to see the whole day's CO2 ppm chart. Many of the best scapers I know adjust CO2 by eye. and those levels I've measured have been similar to my own.Then once the tank is doing well, then you go back and measure the CO2, whatever it is, it is. I have no set ppm level I adjust any tank to.
I'm skeptical that they are 20ppm..........plants are really growing fast and that does not happen merely by magic, only a few things can produce those pearling plants and rates of growth, when I've set my levels at 20ppm, I've also adjusted the lighting a lot........... I do not get those results and this is consistent. My horticulture, dosing, light etc.none of that is the cause, and when I tweak the CO2 right......all is well and the tank grows any and everything well without algae and at the same levels as those Videos.
Now why is that?
My fish also seem to have little issue with these CO2 levels, they breed and I have higher stocking levels than ADA.
So those levels are not toxic, what is really going on is poor methods/testing procedures for measuring CO2? Likely so. But who knows.
To do it the best possible way, you'd need a standard reference that is KNOWN, then a good resolution method, then measure it over the time interval of interest: the entire photoperiod.
This is a plot from a client's tank(the Behemoth actually)
I would say flow relative to the same size is similar as far as CO2 etc as a typical ADA tank.
This was referenced several ways to make sure. Lighting in that tank is low, but at the top, it's fairly high.
The Dutch NBAT members also play a trick, do big water changes BEFORE...........folks come over, since they are graded on purer water= more points. This obviously helps and if my business depended on it.........and looking as good as the pics, you bet I'd do this before.....anyone shows up. I'm not him obviously but that is what I'd do.
Many of the displays are also, quite open, having fewer plants that block flow........but there's plenty of examples where low flow and nice looking tanks mix well, but these also lack good stocking of fish. Which as you also know.....ADA's tanks are sparsely populated. I like fish, I like higher flows(but not always), I have different taste, with less flow, you will run a higher risk of gassing fish and not be able to support as many fish. Tetras can handle quite tough conditions really. I do not see any challenging species being kept.
So lower flow, might be fine........CO2, well, if you do good size water changes often, that can make up for it. I have an ADA store locally where I've already done this, their tanks are jamming with CO2 at AFA............The canister filtered tanks do not degas much.......so the ppm's build up, much like a sealed cap.
AFA CO2 ran in the same 40-60ppm.........ranges.......
I noted this when measuring the difference between the CO2 in the canister vs the wet/dry CO2 graph.
Even at night, the 180 Gal had 20ppm of CO2 and about 80ppm during the day. The CO2 method check in at 2ppm at night after about 30-45 min after the CO2 stopped going in. Stayed there till I added more the next day. Canister filter? Sucker adds CO2 I suspect a little, but the surface exchange...........is greatly reduced for CO2, more than O2, but O2 takes a hit of at least 1-2ppm. Again, it depends on WHEN you measure O2........if you measure it at the peak of growth, it will be higher........by predawn? Then that is it's lowest ppm.
I used a simple KH reference cell, flat tipped pH probe and silicone gas membrane. This is responsive and checked well with the CO2 reference and a RO/DI+ KH reference reference system.
When I did a large water change on the 180, the CO2 dropped to 10ppm...........took about 1 hour to get back up to 70ppm. But plants where expose to air and plenty of CO2 during that time.
I do not know. I'd have to measure the tanks there to say much. I have only the experience here, and with other folk's tanks, the one ADA vendor here........based on what I found from the sediment test, the Light test, liquid ferts test, I'm a bit more skeptical than most, but those test also shows a lot more WHY.........those systems worked well and scaping/horticulture skills alone can help some, but not like that.........now lights will not change here to Japan, nor will the soil....nor will the ferts............but..........CO2 can be VERY different user to user and measuring it also, can vary a great deal. We all thought that ADA had much higher light intensity than prior, till we took a light meter to the fixtures with a nice ADA scape at the vendor. Now we know it was actually quite low.
So there is not much left out of this debate other than CO2 really.
We can reasonably test/measure the other factors/rule out things.
CO2 is tough.
I will not argue that!
