I just recently bought some plants for my 20 gallon tank, just 3 of them (radican sword, micro sword and water sprite) because I was hoping to lower the nitrate levels, and also because I really like the look of a planted tank and want to start slowly. Well I've been reading up on plants, and now I'm scared! Originally I had heard that you need a CO2 tank to add the CO2 to the aquarium, but then some ppl on here had said they didn't have one and theirs were doing fine. But today as I was looking up info on plants, I found out that plants can take the carbonate from the water, split it to create CO2 and greatly increase the pH!!!! My pH is already high! And then, at night, the pH drops again. I know these pH shifts aren't good...

So now I'm scared for my fish! What can I do? Is this really a big problem? Is there any way I can add CO2 to my tank in a relatively inexpensive way? I looked into those CO2 devices, and I know they're expensive

sigh

I have plants, and my pH is no different than when I didn't have any. I don't have a CO2 tank and my plants are healthy and growing fine. I don't think you need a CO2 system unless you really want to get into plants in a big way. There are many plants that grow well without CO2 addition. You can add Flourish Excel to your tank, its a liquid plant suppliment that provides carbon, I've got some but haven't used it yet.

http://www.drsfostersmith.com/product/prod...3221+2147013391

There are also CO2 systems that you don't need a tank of CO2 gas for, like this one that uses sugar (and its also relatively inexpensive)

http://www.drsfostersmith.com/Product/Prod...3565&in_merch=1

I haven't used one of these so I don't know how well they work, but its worth checking out.

Radican sword likes a rich substrate, so a good plant substrate and fertilizer tabs will help grow nicely. Micro swords need a lot of light and laterite in the substrate, and are rated as being "difficult". Water sprite also needs a lot of light but provided they have that requirement are rated as "easy".

Good plant info website:

http://www.tropica.com/default.asp

Hope this helps a bit!

Hi Bonkers

You're quite right about plants and CO2, but the thing is that 3 plants wouldn't even make a dent in the CO2 or pH in your tank (unless you have masses of algae in there as well?). You'd need a veritable forest of them to really make a noticeable difference. And no, very few aqua plants actually *need* extra CO2. Sure they like it if you provide it, but only a very few extra-fussy little buggers can't live without it, so I definitely wouldn't fret about that.

I'm curious about your pH going down at night though... how far does it sink?

Hi everybody,
Thanks for your responses. And Emma, I love your sig! That cracked me up.

Well, my pH hasn't changed as far as I know. I just read somewhere that the pH *would* change at night, because the plants would stop photosynthesizing, thus stop breaking the carbonate into CO2 (and stop raising the pH). I was just worried because, although I only have 3 plants now (which are steadily being eaten by my goldies ) I am planning on getting many more, possibly semi-densely planting up my tank. I knew they might need some CO2 added, but I never knew they could change my pH! That kind of worries me. It is a relief to know that my 3 little plants won't do any harm though...

valkyrie, thanks for the info and the link. Very helpful!

There's alot of us that have planted tanks and do fine without the CO2 stuff,etc. The trick is READING!!!!LOL--If you do your homework,and then buy your plants-it will save you loads of frustration,and money to boot!(wish I would have known that! ) I have never seen my ph lower at night,so I have no clue on that one!

I have a 29 gl tropicals tank, fully planted, and I don't have a CO2 system either. Got Flora base as substrate, have that under the gravel, and use Florish Excel every now and then, thats it. Other then that, the plants have a bit more than 2 watt per gl of water, and they are growing very nicely....

Also the CO2 uptake by your plants will be limited by the amount of light on your tank and by the availability of macro and micro nutrients. You shouldn't worry. In a heavily planted tank with high lighting and available nutrients then yes, the pH will rise quite a bit but in a lightly planted tank with what I'm assuming has regular lighting there should be little change.
If you so desired you could build a home made CO2 generator. They are really quite simple to build and I could give you more info if you like. But as I said before, it is uneccesary if the plants are limtied by other factors.
Congatulations on the addition of a personal salad bar for your goldies. They'll love it.

plant does give out Carbon dioxide.. but that's when in the dark when there is no light for them to make food out of nitrAte..

Carbon Dioxide indeed produce carbonate acid.. and that bring DOWN the PH.. but not to worry.. have a tank light will lengthen the process of phtosynthesis, the process of making food out of nitrAte and this produce more Oxygen..

to reduce the impact of carbonate acid, do have buffer like coral or shell.. or change water regularly.. or u may add baking soda every now and then.. but with your water that is already high PH, then u dun have to worry.. imagine my tap water is totally 7.0.. any slight change will drop my PH!!! thus I need to buffer my water all the time..

dun be scared..

by the way, I dun use CO2 system.. i have my tank 30% filled with plants!! and PH doesn't drop at night.. my PH is caffected by other factor and very unlikely caused by the plants...

I would say, with proper lighting, your plant is VERY benefitial than to cause any harm to your tank...

let me count the benefits
- reduce nitrAte
- produce oxygen
- serve as a source of food/snack to fishes
- hiding place
- BED (yes, some of my fish sleep ON/INSIDE the bush)
- looks pleasant

Negative points of plant.
- Naughty fishes.. always make a mess out of it. extra work to scoop out loose leaf
- loose leaf tend to rot and produce ammonia n even cause PH drop, so scoop out any loose leaf and dun let them rot
- produce carbon dioxide at night.. but so?? I have 4 air stone blowing hard into the water, so I could use that bit of carbon dioxide..

Phew! Thanks everyone for helping calm my fears. I don't know what I was afraid of anyway, because between my snail and my two goldies, those plants never stood a chance I can't believe how quickly they can eat up big plants! It's truly amazing hehe

I think I will just have to try and either 1- add so many plants they can't possibly eat them all or 2- make sure to feed them lots of vegetables so they won't want (I hope!) to eat my plants as much. Or both

Thanks for all the help everyone. Troyjames, I would be interested in seeing how I could home make a CO2 generator. I'm not the handiest, but I could give it a shot. And if it isn't going so well, I'll see if I can con my dad into helping me!

Devs-I definately plan on looking into the plants more, do you have any suggestions of where to look, or what books to read? There isn't much around here (at libraries or at stores) so I'd probably have to look online. Thanks so much!

I think I'm hooked though! After I placed my plants in my tank, I just fell in love with the way they look. So much better than fakies, and they move with the current. It's very pretty!