How can I stabilize pH?

[mordor]

Despite of my all efforts sooner or later pH in my tanks goes to
about 7. I have added driftwood, I got peat in my canister filter, I
use Carbo Plus CO2 system. Even if I made peat extract it will go
down to 6 but after week it's back at 7. I used chemicals once but pH
went below my test's scale and I lost all fish in this tank so I am
trying to avoid all this pH down stuff.

I measured it yesterday: 6.7. I am using mostly RO water sa KH is
about 20ppm and GH is 60-80 ppm.

 

[Neil]

mordor,
The peat in your canister filter should be dropping the pH a little more than that! However, most canister filters have a very high flow-rate that does not allow the water to come into contact with the peat for any significant time. If you want the full benefit of peat, water should be "trickled" over it. It should also be replaced fairly often.
If you have been unsuccessful at dropping your pH, you may want to lower your water turn-over and filtration in general. I do not know the specifics of your tank, but I figure that you have some pretty good movement in there. Slow everything down a bit and see what that gets you. Just be careful not to over-do it. The CO2 may act in conjunction with your "trickled" peat to start driving your pH down too quickly. Neil

 

[erik_dgcc]

Mordor,
Seachem makes a product called Discus Buffer that is real good for lowering your PH and it can also soften your water by removing the calcium etc. You can use it in conjunction with their Neutral Regulator to achieve a PH you desire (a chart is given on the side of the jar). The products don't contain Phophates eighter.

Erik

 

[mordor]

Good point Neil. I heard that some people put peat into bag then directly into aquarium. I may try this too. I removed larger stones since I do not know if they are marble, lime or something else. I will put more driftwood and coconuts instead. I have to look for oak leaves during my trips. I have heard that these collected after winter are the best.

 

[mordor]

Erik: I tried Kent stuff once and killed all my fish in tank. I may consider Seachem since I have bought pH meter.