Carbon Dioxide (co2) Question

[thefishycouple]

Hello,
I have a 30G fish tank and my water currently has a pH of 6.8-7.0 and a kH of 3-4 (Which gives me a CO2 level of 10.5, which is green). I've been injecting CO2 through Red sea's Turbo CO2 system for the last week now and thought I had enough CO2 in the water but apparently my plants weren't doing very good. I then decided to buy a Red Sea's CO2 indicator, and it reads that I do not have sufficient CO2 in the water. Is my CO2 level fine or is the reader broken? Please help before I lose more plants.

PS: Currently I have a couple swords and Javas, Rocks and Slates and Drift wood. I've been adding 1/2 a cap full of Flourish Excel daily, I have Flourite Gravel and add API's root tabs monthly.

 

[Alex_]

lighting?

 

[thefishycouple]

lighting?

......

If you mean how much, then 2.75 WPG and it's on for 11 hours a day

 

[Dave Spencer]

With the info you are giving, you are running a high tech set up on low CO2 and minimal biomass. If dying plants are your problem, please tell me your secret for keeping algae at bay.

CO2 is difficult to measure, particularly if you use kDH in relation to pH, so you might want to read this:

http/www.fishforums.net/index.php?showtopic=169942

You might want to look at getting a pressurised system for a stable CO2 at 30ppm.

 

[thefishycouple]

Thanks for the reply.

The tester I have measures the co2 exactly like the one in the link.

I've had the same set-up co2 and reader (Red Sea's) for months now. It used to work fine, giving me "green" readings and I changed the liquid in the tester in order to keep the readings accurate, I even bought a brand new co2 emmiter. Lately no matter how many water changes, fresh co2, or liquid tester I put in the tank I'm only receiving blue readings. The tester shows that the co2 is low but the mathmatical way (co2 table) of measuring the co2 through the ph and kh states that it's fine.
Any other ideas on how to get an accurate reading? or what could be affecting the co2 level? Thanks

BTW I have a little bit of green algae growing on some spots on the gravel and over a slate, and I'd love to get a pressurized tank but the money won't allow for it right now...

 

[fishboytoo]

What type of filter are you using? I have recently been successful in raising my chronically low co2 levels by switching from a HOB filter to a canister. I was getting about 10ppm before the switch and now just took a reading a of 28ppm, and it has been consistantly high without fluctuations. It may be something to consider, and much cheaper than a pressurized co2 system.
Good luck.
FB2

 

[thefishycouple]

Had no idea filters would have such an impact on co2 levels...
I'm actually using a Penguin Bio-Wheel 200, but like I said before, I have very little cash right now and hope my solution is a few bucks away.
Any other suggestions?

 

[Dave Spencer]

I have just Googled your filter and it looks like a HOB to me. Sadly, this system will drive off most of your CO2, making it far less effective a set up for your plants.

 

[thefishycouple]

I understand that by having a canister filter I'd be better off since there wouldn't be much agitation on the surface.
But would that fix the problem I am currently having?
Thanks

 

[mikey12421]

I understand that by having a canister filter I'd be better off since there wouldn't be much agitation on the surface.
But would that fix the problem I am currently having?
Thanks

I use a hang-on-back and redsea canister and am doing fine. (in fact my growth is so high I almost can't keep up with the trimming) Have you tried raising the water level so that the agitation from the HOB filter is minimized? Also, IMO, if you have a heavily planted tank you are going to want to take the wheel out of the filter - it will deplete the good along with the bad. I use my HOB filter (biowheel sans wheel) only to keep the water moving and to remove particulates. A canister filter is a good idea, but as above I would remove all non-mechanical filter media - you shouldn't need it and it will actually stunt plant growth.

Couple of edits: By "deplete the good along with the bad" I was not referring to co2, but macro nutrients (just wanted to make that perfectly clear).

Also I'm assuming you've tried replacing the sugar and yeast in your reactor. If not try it, sometimes I mix it up and mess up on the proportions because I am not paying attention and end up with a bum mix. Those RedSea pumps are hard to judge because they sometimes spit out regular air bubbles along with co2 when your mix isn't right. Check by removing the tube from the pump and placing it in the water. You should be getting a large bubble every few seconds if the mix is right.

Those redsea pumps are also kind of fragile. If you mess with your tank while it is running it can get crud in there and crap out on your altogether. Try running your co2 system in a small tank or vase (<5 gallons) and seeing what you readings are. Try and observe the pump and see if its crapped out. If it is has it won't make that squishy noise that it makes when it releases a cloud of bubbles.

Also try and replace the tubing, that stuff wears down pretty quick when exposed to pure co2.

Mike

 

[thefishycouple]

Are you sure about the bio-wheel? I heard it is a must for bacterias and such...
My water is in the highest level also
I explained above that I bought a new co2 system (Red Sea's) that's because it just gave up on me one day...
Well, I'm sick of this problem so I had time today after work to check out why my older diffuser was no longer working, ended up it was filled with nasty stuff, i'm guessing co2? but anyways, it's working now so I'm giving it a shot and having both units working at the same time. What I will definetely do is change the tubing on my older unit since it's all fogged up
Thanks

 

[mikey12421]

Are you sure about the bio-wheel? I heard it is a must for bacterias and such...
My water is in the highest level also
I explained above that I bought a new co2 system (Red Sea's) that's because it just gave up on me one day...
Well, I'm sick of this problem so I had time today after work to check out why my older diffuser was no longer working, ended up it was filled with nasty stuff, i'm guessing co2? but anyways, it's working now so I'm giving it a shot and having both units working at the same time. What I will definetely do is change the tubing on my older unit since it's all fogged up
Thanks

I'm no expert, but i'm pretty sure about the bio-wheel. As I understand it, plants are nature's filter. The plants convert ammonia to nitrites and then nitrates, as do the bacteria colonies. In the non-biowheel tank this bacteria forms only on surfaces such as as the substrate, rocks and wood (or decs if you have). The bio-wheel works well in the non-planted tank because you add a higher amount of surface area on which the bacteria can form (the biowheel) and thus increase the nitrifying effect in the tank. In a planted tank the bacteria still forms on the substrate and tank decorations, but now the bacteria is competing with the plants for the beneficial ammonia. If you then add a biowheel, you are in effect increasing the amount of competition that the plants have for the ammonia. Instead of splitting the ammonia among two sources (in-tank bacteria and plants), you now have three, albeit that the biowheel doesn't have near the capacity for bacteria that the substrate does.

Essentially, the plants are doing for your tank what the biowheel would be doing if you had no plants.

Anyway, if anyone more experienced out there knows differently, please let us know.

Hope that helps,

Mike

Quick edit: I've googled planted tanks and biowheels and found conflicting info. Most seem to say don't use them, but some say they like them. Just about all agree that the biowheel itself does drive off a signficant amount of C02.

 

[thefishycouple]

Your explanation sounds good to me.... I'll give it a shot.
Thanks

PS:

Anyway, if anyone more experienced out there knows differently, please let us know.

x2

 

[thefishycouple]

My filter agitates the water surface way too much, so my friend just gave me an Eheim 2215 filter to try out.
What do you guys think about that filter?
My filter is 30G, Am I going to possibly over-filtrate the tank?
Please leave any comments

 

[SNAIL]

No, you won't over filtrate your tank. The bio wheel does drive off CO2. Don't use activated carbon in your filter as it will take all the nutrients that the plants need. Use a sponge or floss pad to remove large particles with your filter. The bacteria colony will grow on it too. The bacteria grows in the tank as well as mentioned by others so when you do change your filter media, there shouldn't be any impact on your bilogical cycle if not very minor.