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Co2 2hr rule myth

I planted this cutting of Rotala rotundifolia 'Orange Juice' last night, it's been reaching for the natural light all day.

By 5pm ish it will be upright again as my light comes on at 3pn, on my previous schedule the co2 would have come on at 1pm but as of yesterday it's 7am.
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Okay, I think I take your point...How many problems occur because folk are not aware that their tanks maybe getting too much direct sunlight or strong ambient light?
Rooms with windows have ambient light. But that's not usually a problem since it's usually not strong enough to exert an influence above and beyond that of the artificial light we use to grow plants.
If however, a tank is sitting in a south facing window then it's likely to get strong ambient light and direct sunlight, and that may cause problems.
Solution...don't place an aquarium in or near a window...unless it's one of these ;)
https://www.ukaps.org/forum/threads/the-banyan-forests-of-stickleback-island.12557/

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Okay, I think I take your point...How many problems occur because folk are not aware that their tanks maybe getting too much direct sunlight or strong ambient light?
Rooms with windows have ambient light. But that's not usually a problem since it's usually not strong enough to exert an influence above and beyond that of the artificial light we use to grow plants.
If however, a tank is sitting in a south facing window then it's likely to get strong ambient light and direct sunlight, and that may cause problems.
Solution...don't place an aquarium in or near a window ;)
I'm not great at explaining my trail of thought in ways others may understand lol

But yes, no house is pitch black all day so the tank will get some form of ambient lighting be it natural or artificial.

It was looking into blacking out the tank that started this trail of thought and got me to look outside the tank for problems instead of going around in circles with the internals.
 
Sort of thinking outside the glass box ;)
Literally,

I have been as sure as I can be that I'm doing everything as I should in the tank with co2 etc etc but nothing was getting any better with algae, yet the plants all grow like mad even buces were sprouting shoots all over the place.
 
Also the 30ppm that is written all over the place, isn't a rule written in stone.. There are people saying they are only adding 15ppm CO² and have equal good results.. Now i have to say maybe, since i can't know, but you have to try things. And since if you recieve a lot of natural light, than this will be also not a stable light source during the year.. You can't realy anticipate to this with a fixed on off schedule. Then try for example 15ppm CO² for 24 hours a day and don't switch it off at night.. That's what i would try if CO² is an absolute must have in natural light conditions. :) Than at least it will be stable for the whole periode..

I'd echo this.... try your co2 at a lower rate for 24/7. It sounds like it would work well for your setup. You might be surprised by how even a very low injection rate provides benefits (assuming you have distribution nailed).
 
I'd echo this.... try your co2 at a lower rate for 24/7. It sounds like it would work well for your setup. You might be surprised by how even a very low injection rate provides benefits (assuming you have distribution nailed).
I did a brief ph profile and checked it against the ph/co2 chart which came back as off the scale lol

Through trial and error I have the co2 as high as I can without the fish gasping at the surface so know I'm at my max level for it, distribution is in my mind great and diffusion is inline.

In terms of running it lower for 24hrs I would rather not as I do like to give the fish etc a break, plus at lights off the tank is in total darkness anyway.

I'm more focused on matching it to lighting now which I am doing based purely on the plants reaction to natural and ambient light rather than the tank light.

The tank wakes up at 8am ish so I'm running co2 from 7am, because I know I'm at the top end of injection I'm expecting the impact to be quick so starting 1hr before the tank wakes up and not 2hrs, also because I'm working purely based on my own assumption and not a given method as the standard 2hrs before lights on is.
 
That all sounds good, you've found an aporoach that works for you, so I totally aporeciate you not wanting to try 24/7.

I'll address one point though, for the benefit of others who might consider it.
In terms of running it lower for 24hrs I would rather not as I do like to give the fish etc a break, plus at lights off the tank is in total darkness anyway.

When advocating 24/7 my intention is low co2 throughout. As it never gets high, the the fish don't need a break.
 
That all sounds good, you've found an aporoach that works for you, so I totally aporeciate you not wanting to try 24/7.

I'll address one point though, for the benefit of others who might consider it.

When advocating 24/7 my intention is low co2 throughout. As it never gets high, the the fish don't need a break.
The only benefit I can see of running 24/7 is having that added co2 when the tank wakes up which is where I feel the standard 2hrs before lights on ignored, there is no benefit of co2 over night so it can only be that the potentially ignored time is then covered.
 
Anyone that has their lights and co2 synced to say 5pm for example is potentially neglecting the need for co2 from when the tank wakes up, in my case 8am ish but will differ from room to room of course.
 
Lets work with an example of my theory based on summer time,

So lets say a room gets enough ambient light to "wake up the tank" from say 6am until say 10pm, 16hrs total

Then the tank light is run from say 4pm until 10pm, 6hrs

Co2 run from 2pm to 9pm, 7hrs

If the tank is awake and plants photosynthesising from 6am which is the desired affect we aim for by using tank lights right? then is there not a deficit of co2 between 6am and 4pm? 10hrs

If the tank wakes at 6am then based on the 2hr principle should the co2 not start at 4am?

Make sense?
 
f the tank wakes at 6am then based on the 2hr principle should the co2 not start at 4am?
It should , depending on ambient light levels, 16 hour daylight is just in midsummer though.
Basically if there is a lot af ambient light, the best thing to do ( in my mind) would be: start "CO2 at sunup ( stil low light, gradually increasing) 2 hours after sunup start tank lights, keep them on for 6 hours, then kill the tank lights and have the ambient light only. After those 6 hours the plants will stop the largest part of metabolizing (they "ate"their fill) and won't be hurt by the diminishing ambient light.
 
It should , depending on ambient light levels, 16 hour daylight is just in midsummer though.
Basically if there is a lot af ambient light, the best thing to do ( in my mind) would be: start "CO2 at sunup ( stil low light, gradually increasing) 2 hours after sunup start tank lights, keep them on for 6 hours, then kill the tank lights and have the ambient light only. After those 6 hours the plants will stop the largest part of metabolizing (they "ate"their fill) and won't be hurt by the diminishing ambient light.
Awesome you have made sense of my theory lol
 
I have two tanks one takes 3hrs to get the pH drop whilst the other does it in 45mins. The one that takes 45mins a 500l tank does have duel CO2 reactors with a massive CO2 injection rate, once the pH drop is reached one of the CO2 injections is off then for the rest of the photoperiod, a 6Kg cylinder lasts about a month



The smaller 50l tank just has one atomizer and the 6kg CO2 cylinder has been on it about nine months
 
I also run CO2 24/7 - despite tank not being adjacent to the window, sunlight directly hits the tank from sunrise to ~noon

I've never run pH profiles on my tanks, water is extremelily soft so I'd have to adjust tap water & I gave that up some while back ;) - low level 24/7 CO2 is dead simple & neither plants nor fish seem to complain

Conversely I've never had much algae in this tank even with erratic CO2 & erratic photoperiod & at most 4x tank turnover/hour (flow distribution is decent)

If you want that high tech "ready in 8-12 weeks" aquascape that's not somewhere my lackadaisical approach will ever get you :D
 
I planted this cutting of Rotala rotundifolia 'Orange Juice' last night, it's been reaching for the natural light all day.

By 5pm ish it will be upright again as my light comes on at 3pn, on my previous schedule the co2 would have come on at 1pm but as of yesterday it's 7am. View attachment 113150
Not sure how viable the difference is but I'll post another in the morning to show the affect of natural/ambient lighting.

This is only a 3" cutting though.
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Rotala rotundifolia varieties are the most flexible aquarium plants :D
 
I run 24/7 co2 in all my tanks, they all get natural light, one is even outside, they all do great with this method. All my fish and shrimp seem happy never had any problems with them gasping, 24/7 co2 at a low rate is worth a try if you have lots of natural light hitting the tanks.

I stand by this method, i have basically no algae in all tanks, even the tank outside (picture below, its way overgrown) has no real visible algae .

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IMG_0847 by Colm Doyle, on Flickr
 
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