co2 level ok?

[aqua]

hi

recently i did measurement on my c02 level using ph/kh test.

seems like 1 hour into injection the ph is 7.1, 4 hours the ph is 6.9, 9 hours the ph is 6.7.

so is this consider as inconsistent c02 injection?

i am using internal reactor, my kh is about 3. i have to crank the co2 bubble rate to about 4-5 bubbles per second to achieve 6.7 ph near the end of the photo period.

i am experiencong some bba near the filter outlet and some thread like algae on some patches of the moss. the thread like algae is black in colour and when i put it out it looks like entangled hair?

my dosage per week is

1 tsp of KNO3 twice weekly
1 tsp of K2SO4 twice weekly
5 ppm of KH2PO4 twice weekly
10 ml of easylife liquid fert twice weekly
photo period 10 hours

so what should i do to eliminate those algae?

cheers

[budak]

The cheapest, simplest way to go is raise your KH to 5-6. At this KH level, without having to crank up your regulator further, you will get a much higher CO2 level (20+ mg/l). Assuming all else is fine (plants growing, fish swimming, sun shining) the BBA should diminish in a couple of weeks.

5 ppm of KH2PO4? With just 1 tsp of KNO3? How big is your tank? And your lighting?

[chua]

Hi,

Maybe you want to lower your pH further. For my case, i also had a kH of 3 but i push my pH all the way down to 6.4 or slightly less during the photo-period.

As for the inconsistant in your pH, i think it is pretty normal. Unless, you are using a CO2 controller. you will not be able to obtain a steady pH value.

4-5 bubbles for second, how big is your tank?

You may want to adjust the outlet of you internal reactor, to minimize CO2 loss. For my case, it really helps.

Thanks.

[aqua]

hi

oops sorry should be 0.5ppm for KH2PO4. mt tank is 4by2by2.

cheers

[PeterGwee]

Keep the CO2 in the range of 25-30~35ppm. Add more flow to the reactor and set your filter outflow near it. You should be able to hit the good CO2 range within an hour or so...if not, try to find ways to mix the CO2 better (external reactor barr style..feed CO2 into a powerhead and then output into an external reactor. Smaller tiny bubbles..more surface area of contact..faster dissolution rate and response time.) and mix the rich CO2 water well in tank.

Regards
Peter Gwee