Hi. I'm new to this forum and I really like the scientific aproach you guys bring to the hobby.

My question is about photoperiod.
I don't know much about the subject, but I've read about photoperiod governing much of plants actions (e.g., flowering, vegetative growth). In aquaria literature I've also read that plants aren't able to use light nonstop, thus long photoperiods being favorable to algae growth, since they are able to do so.

So, does ambient light in the room of the aquarium interferes with the plants photoperiod, and may it also stimulate algae growth? I ask this mainly because my tank's lights turn on at 12:00 and stays until 22:00. The tank is located at the living room of my apartment, far from the windows, but the room gets iluminated from the sun in the morning and also from lamps and TV, probably till midnight.

Regards,
Bode.

Lamps probably not causing any issues, the sun inj the miorning certainly can if the CO2 is not also on at that same time.
Sun is about 10X stronger than the light we use

Regards,
Tom Barr

I don't think this is true. Plants are able to use light nonstop for 8 hours or more, but not a lot more. Algae are far more opportunistic than plants are, so would be more likely to benefit from split lighting periods than would plants. The numbers I have read the most often are 8 - 10 hours for the plants, with no interruption.

First of all, thanks for the answers...

I have CO2 from a chemical reactor (HCl + NaHCO3) running the whole time - I'm too lazy to regulate the flow every morning and the power head I use to dissipate it in the water doesn't work if it gets too much air inside, so I can't plug it to a timer. Also, no direct sunlight at all.

Sorry if I wasn't clear. I meant nonstop as a really long period of time, like 24 hours or more, and not just 10 hours nonstop.

As an exemple, if you interrupt the photoperiod (I don't know how long or what drop in intensity it would take), dividing it in two, the plant may interpret it as if the days have gotten shorter.

I was wondering if the intensity of the room's ilumination would be interpreted by the plants as photoperiod, so my plants would be exposed to a photoperiod of lets say 15 hours (8:00 AM to 23:00 PM), not fully using the final hours of light... I don't know if I was clear enough...

Regards,
Bode.

Best thing is to use DIY yeast instead of soda and HCL.

Cheaper and easier to handle.
See the DIY internal venturi reactor design I have in the articles and DIy section.

Simply plug the powerhead running the CO2 into the light timer, when the light comes on, so does the CO2.

Otherwise the CO2 bubbles out the top and is not dissolved.

Simple on/off approach that does not require you to stop the reactor or biological prcoess for each source of CO2.

10 hours is a pretty good ideal time for lighting.

Close the blinds, or cover the tank with a towel etc and take it off when you get home later at night.

Regards,
Tom Barr

yeah, I guess covering the tank is not a bad ideia...

I prefer the acid method. In my nano (40 liters) it lasts longer, is easier to adjust and does not leak into the tank.

Of course it is a little more expensive (but not really expensive - maybe 4$ a month) and has the risk of exploding (highly unlikely). Manipulating the acid isn't a real problem.

I have read your suggestion of pluging the power head to the timer in other thread, but it doen'st work here. The PH get filled with CO2 and has trouble starting in the morning. I would need a different design in order to keep the CO2 out of it. Or a new pump that has no problem in starting when filled with air.

Regards,
Bode.

The internal venturi reactor that Tom designed and is described here will not fill with anything except water. The excess CO2 bubbles out the "burp" hole on the side, and the powerhead inlet is always in the tank water, keeping it primed.

bode, try tilting the powerhead sideways, the pump will not get the air lock that way.
But when it's on, it'll still suck the CO2 in.
Most designs do this(Mine, Venturi skimmers etc)

Regards,
Tom Barr

Hey guys, thanks for the answers... i havent replied sooner cause i stoped being noticed of replies... strange.

Anyway, i have solved the problem of airlocking by puting the CO2 hosea little of the entrance of the pump, so it can suck the gas only when it is on. If i can borrow a camera, I ll post some pics. I have tried the ventury, but to no sucess.

Well, in the meantime from my last post, the algae is under control - I was having a terrible bloom of green water - and I haven't done anything about the indirect sunlight, jusk kept high CO2 and ferts. I guess the indirect light doesn't affect the aquarium as much as I thought.

After years of resistence I have tried the yeast method, and have been using it ever since, mainly because it's so easy to refil.