Malawi cichlids, plants, KH and CO2

[gpontis]

I have a 125 G planted tank with Lake Malawi cichlids and clown loaches. Lately I have been doing a great job growing algae, BBA to be specific. Tom recommends jacking up the CO2 to 30ppm for best results when it comes to plants and algae.

After looking at the charts relating CO2, KH, and pH ... it looks like it would be difficult to get the CO2 up to that level without letting the pH drop too much or increasing KH a lot. My fish have lived at ph=7.2 KH=10 for a long time and they seem to be doing quite well, one has even had a healthy batch of babies twice in the past year.

Most Malawi fans would aim for pH 7.6 or higher, but if I was to settle for 7.2 then it would call for about KH=19 to compensate for 30ppm CO2. Or I could let it drop to 7.0. Seems pretty far from native conditions for these fish.

Any comments or guidance ? Has anyone here tried this before ?

George

 

[imatrout]

Re: Malawi cichlids, plants, KH and CO2

I had the same issue when I was growing Tanganyikans in my 150. You can search and find the old posts if you want. Whay I did was add baking soda to drive my KH up to 14 -15. That way I could add a lot more CO2 without lowering the Ph too much. Tangs are more sensitive to lower PH than Malawians are.

For grins, you shouls check out this link http://dump.fibervault.com/Tank_Oblique_251204.jpg

Thi si sTravis' 125 planted Malawian tank. It's awsome!

 

[gpontis]

Re: Malawi cichlids, plants, KH and CO2

Thank you for posting this. The picture of that tank gives me the urge to try harder. If I could get one quarter of that result I would be delighted. However, I do have a much larger fish load which is counterproductive. Maybe time to get rid of the electric blue bully in an effort to scale back on that front.

Meanwhile, I'll try escalating the KH and CO2 and see how it goes.

 

[Bill]

Re: Malawi cichlids, plants, KH and CO2

I had a planted tank with mostly peacocks and the pH went up and down from 7.2 to 7.0.

When the pH was 7.0 I saw no ill affects or color changes in my fish. They would breed at these conditions and the fry were healthy.

I did add baking soda at every water change to keep my KH high.

Bill