plants effect on pH

C

chilligirl

AC Members
Nov 9, 2007
119
0
0
So I just tested my water for the first time in a few days, and my pH is up from 7.0 to 7.6!!! :eek3: Fish are all fine, fwiw. Ammonia 0, Nitrites 0, nitrates down from trace to not registering.

The only thing that's changed since the last time I tested is:

increased lighting
added some live plants
added a pair of kribensis

I'm not doing any CO2 supplementation. So, after mulling it over and thinking about the chemistry of it, it seems most likely that the pH change is due to there being less CO2 in the water since the plants are using it? (which would be supported by my nitrates disappearing).

I'm inclined to shove some more peat moss into my filter, or even mix a bit into the sand around the plant bases, but thought I'd check here first.

What do y'all think? Should I try to bring it back down to 7 using peat moss? Should I just leave it? Is there any way to add more carbon to the water for the plants that doesn't involve pressurized canisters or the DIY setups? I REALLY want to stay low tech at this point...

All of my fish prefer a slightly acidic pH and softer water...
 
Your Ph is fine, if you want to add some carbon without co2 then try some Excel.

http://www.bigalsonline.com/StoreCa...84-def-USD-18480##0##e&query=flourish&offset=

img3041188med.jpg
 
thanks, I think I'll try the excel. I'm already using regular Flourish, which has micronutrients, but not carbon.

And, while my pH is alright, I'd prefer to have it at 7.0 or slightly below for the fish I keep, especially as I plan to eventually add in a pair of GBR. It's 7.0 out of the tap, and 7.0 in my goldfish and betta tanks. It was 7.0 in the 90g also until I added the live plants.
 
The excel will add carbon for your plants to use, but it won't lower the ph like co2 will.
 
If my pH was 7 until I added the plants though, and I presume the pH went up because the plants are getting carbon via the CO2 in my water (so they're removing CO2, which leads to a higher pH), if I give them an alternate source of carbon, won't my pH go back down? Or, at the very least, respond to natural buffering via peat moss?

If I DID get into DIY CO2, how long would a 2L bottle setup last on a 90G tank before I'd need to refill it? I suppose I could fit it in the area under the tank, with the canister filter and python, I just worry about it getting knocked over (although maybe I could put a bracket on the wall...).

Hmmm...going to go read about DIY CO2. Although, is it even worthwhile with low light? I've only got about 1.6 watts per gallon, although it LOOKS very bright, and it's all HO lighting...
 
man im the first to post a answer to your co2 ?. you going to get alot of answers lmao. I did.

heres the basics you need to answer you ? -- im sure your going to read everything you find too.

but it only works with a combo. light,co2,ferts. if one of those is outta whack look out for alage.

and on 90g, a pressurized system is best.
on a 90g you'd need like 5-6 2L's
 
well, the more I read about CO2 in general, and especially the DIY setups, the more I want to run screaming, lol. It just sounds WAY too complicated, time consuming, and easy to mess up, for me.

So, I guess the question is, will Flourish Excel be an adequate replacement for CO2 in my tank?

Also, can someone provide a link to an explanation of the relationship between plants and algae? I don't quite understand it. It seems to me that algae thrives on the same things plants do (light and nutrients), as evidenced by my goldfish tank, where plants that aren't eaten thrive (despite pretty low light), and algae grows in abundance!
 
Your pH went up because your plants have used whatever ambient CO2 was in the water. The reduction in CO2 in your water increased your pH. Once CO2 is gone certain plants can convert bicarbonates to carbon, the risk here is without a water changes you could have a massive pH drop due to reduced buffering compacity. That will kill fish. I would consider that unlikely, but possible. pH changes caused by CO2 should have little to no effect on your fish, as fish are not as sensitive to pH changes caused by CO2.

With a 90 gallon tank you will be buying an extreme amount of Flourish Excel to keep the carbon up. Also, the organic carbon in Flourish Excel will not change the pH, like CO2.

I think at 1.6 WPG in HO that may translate to about 2wpg overall, sufficient light for a lot of plants. You really have the option of using pressurized CO2 or not using CO2 at all. See the following link for more guidance in this regard- http://www.barrreport.com/articles/433-non-co2-methods.html

If the pH bothers you, Peat will help reduce the pH. I had the same issue when I upgraded my lighting and added plants without CO2. My pH went from 7.2-8.0. I decided to go the pressurized CO2 route on my 72g. It has worked out well for me, but the plants grow like mad. I bring cuttings (some a foot long) every week to my LFS. The advantage to low CO2 is 6-10x slower growth, less maintenance, less fertilizing, less work. I think you can pull it off without an algae problem in your current setup. If you were at 3wpg you would have to go to pressurized CO2.

Hope this helps

Fred
 
Fred - thanks that does help, and is very consistent with what the plant gurus at my lfs said :)

I just picked up some Excel and some more plants. I got the following:

- a very nice dwarf lily, it's called "red tiger"
- hygrophila polysperma (green)
- hygrophila rosa. (tropical sunset)
- anubius barteri
- some variety of cryptocorne that's very pretty reddish verigated leaves
- some variety of grass

So, now to go and do a big water change, totally rescape my tank, plant the new stuff, replant the other stuff, then take a pic and post it :)
 
You must log in or register to reply here.
AquariaCentral.com
Top Bottom