Trouble getting the right CO2 rate

84Reasons

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Hi Guys, newbie here, first tank since I was a kid, and 2nd post here!

I recently setup a CO2 system in my planted tank. I have a drop checker and all the required tech to regulate it, at the moment I have it going on 30 mins before my lights come on, and for the duration of the lights (8 hours). My drop checker shows as green whilst the CO2 is running, so I assume I am dosing the correct amount of CO2 (not too much, or too little). However, again because I am a newbie, I'm not really sure at what rate my plants should be growing, they seem to be growing, and I have only had my new plants in (and the CO2 system) for about a week, so I know I shouldn't expect them to have grown in already, however I just get paranoid that maybe I need to add more CO2? I have a couple of plants at the front that have gone partially translucent, which I have looked up is lack of CO2, however the rest of the plants are doing fine, so I just assume this is to do with lack of flow of CO2 to that area? I am dosing fertiliser daily using " the aquascaper - complete fertiliser " . I don't have a plant soil (overlooked it at tank setup) but I do have root tabs in, and try to make sure my plants are getting all the nutrients from the water column with my fertiliser. I have 2 x T5 iquatics 24w tropical florescent bulbs which have reflectors on also, these are on for 8 hours a day.

Am I just being paranoid or do I need to add more CO2!?
 

Zeus.

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30 mins to get the pH drop [CO2] before lights on is very rare without a complex CO2 injection method. It normally takes most folk 2-3hrs of CO2 on to lights on to get the pH drop.

Have you done a pH profile?
 

84Reasons

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Have you done a pH profile?
Is this just checking the PH? If not then no, I haven't done one of these. I'm also a little bit worried that the drop checker isn't working correctly anymore, as since I added the CO2 system, it has always stayed green? should it be switching colours every-time the system goes on/off?
 

Edvet

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Check pH hourly from before CO2 on till lights out at least and preferably a starting sample too ( take water out of the tank at the evening and check in the morning so all CO2 is gone and you measure the acid content of the tank)
Lowest pH should be achieved at lights on. The pH drop needed is dependend on lightlevels, generally we like a 1 point drop, less could work with lower lightlevels.
 

84Reasons

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Lowest pH should be achieved at lights on. The pH drop needed is dependend on lightlevels, generally we like a 1 point drop, less could work with lower lightlevels.
So after checking this hourly, you think I should adjust the co2 rate so that over the course of it running for 8 hours, the PH only drops by 1?
 

Edvet

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No it should drop before lights on.( lowest pH when the lights come on, and then stay stable during the day as long as the CO2 is on, and drop after co2 is off)
Adjust slowly though to have the fish adjust to lower daytime levels
You can start with adjusting the timer imediately, adjust the amount slower
 

84Reasons

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No it should drop before lights on.( lowest pH when the lights come on, and then stay stable during the day as long as the CO2 is on, and drop after co2 is off)
Adjust slowly though to have the fish adjust to lower daytime levels
You can start with adjusting the timer imediately, adjust the amount slower
Right okay, I can check that then, probably have to be a Sunday Job! hard to monitor it all day whilst at work haha
 

Edvet

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Good. It will tell you 1) how fast you get to max pH drop, 2)size of the drop, 3) stability of the drop 4) nighttime values so if you need to actively remove CO2 during the night ( plants produce co2 at night, to much and you might need to actively remove CO2 in the night)
 

Nigel95

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I also recommend the ph drop method (or even more like 1,2 but monitor fish and keep enough surface agitation). Drop checkers are trash IMO.
 

Tenochteco

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Good. It will tell you 1) how fast you get to max pH drop, 2)size of the drop, 3) stability of the drop 4) nighttime values so if you need to actively remove CO2 during the night ( plants produce co2 at night, to much and you might need to actively remove CO2 in the night)
After the co2 has been activated during the day, how about doing water changes during the night when the lights are off? I was thinking that by doing water changes at night, you won't alter the co2 hence no imbalance of co2 thus creating or stimulating algae? Any potential disadvantages by doing this water changes at night?
 

SRP3006

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Water changes are best done outside of the photoperiod IMO. My co2 comes on at 12, My lights at 1500. So all my water changes are done in the morning.
I've read that they are best done just before the photo period so that the plants can use the co2 in the tap (if any) and also the co2 they have absorbed from being emmersed. Think I read that on this forum.
 
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