kh and ph

[nitrous]

I think that my kh for my 20 gal planted is relatively low. it was at 5kh last time and my ph is still at 7.6 and hasnt dropped with a month of co2. is it true that it is supposed to drop? also how can i safely lower my ph or make my kh higher to try and get rid of this hair algae? should i stay at 5 kh or try at make it higher also?

suggestions are appreciated

thanks!

 

[resiak]

kh of 5 is not bad; anything under 4 is low I believe. My KH is 5 and my PH is 6.6, from the tap my PH is around 7.2.

 

[Purrbox]

With a dKH of 7.6 and a pH of 7.6 you've only got ambient levels of CO2 in the tank. What method are you using to inject CO2? Is there anything in the tank that might be gassing off the CO2 by causing surface agitation (Airstone, Biowheel, etc)?

The only way to make KH and pH move independantly is through CO2 injection. Anything else will only cause them to move together. A dKH of 5 is excellant for CO2 injection and doesn't need to be messed with.

 

[malkore]

To add to purrbox, Kh is a measure of alkalinity of the water. The more alkaline the water, the higher the pH, since acidic water has lower pH.

The process of using Kh and pH to determine CO2 relies on the fact that they are inter-related. When CO2 levels lower pH by creating carbonic acid, the Kh stays untouched. The deviation of the pH from normal to lower than normal is how we see the CO2 working and measure its levels.

So as purrbox says, you have ambient CO2 levels. Are you injecting CO2? DIY or pressurized? What method of diffusion?

3dKh is the bare minimum for safe CO2 injection, and i usually have people bump to 4dKh as a safety net if they have soft water to start with. 5dKh is actually a great level. plenty of buffer, but not too much, so you shouldn't have to use as much CO2 as someone like me, with 9-10dKh.

 

[nitrous]

just fyi this my 20 gallon tank sorry for not mentioning that and i am using the hagen co2 system which i dont think is pressurized its just like diy but it wasnt made by me so ya the reason for all this is becuase i still have hair algae in my tank which made me stumped. i have the kh and ph like i said and my nitrate was around 10 last check so what else contributes to hair algae?

thanks for the feedback, i thought it was a low kh but guess not, thanks

 

[Purrbox]

Even with that Hagen system you should be getting more CO2 than 4ppm. There must be something in the tank that is causing it to gas off. Even once that's taken care of you may want to tweak that system by switching to a couple of 2 Liter bottles, as the current system isn't enough for that size tank despite what the marketing says.

What test kit did you use to test for Nitrates? Also how long ago did you check? Test strips are notoriously inaccurate and even most liquid kits aren't accurate at measuring Nitrate under 10ppm. It's quite possible that you have closer to 0 Nitrates due to test kit inaccuracy and/or it having been used up since the last time you tested. If your Nitrates have bottomed out this could easily cause Hair Algae.

 

[nitrous]

i have the ap master liquid test kit and i check maybe a week ago and ill check again this friday and i mean it may be 10 give or take 1 or 2 but it wasnt 0 or 5 so i know that it was more near 11 so i dont know. and ive had the hair algae since last test so i dont know and the tank is not covered. 48 watts of light and a ac filter hob