WKLau 寫:
I have bought ADA mud from Fat Tak Fish as the shop operative said it could lower the PH value efficiently. However, I don't totally reset the tank. Thus, I just laid one think layer on top of existing TK glass mud.
The PH value dropped to 6.9 immediately. However, it just lasted for a few days only. The PH value has climbed up to 7.3-7.5 recently.
I can share my experience with you. Preivously, I was using sand as substrate for my 30" tank(140L), PH was 7.6-8.0 and KH was 8-9. I had tried peat moss 草泥丸before, but it can't effectively lower the PH, it just tinted the tank water to yellow. So I try ADA aquasoil. I just take away half of the substrate (~12kg) and replace it with 11 L (1 bag 9L + 1/2 bag of 3L) of ADA aquasoil Africana.The soil is completely sealed the bottom sand, even I pull out some plants, the bottom sand doesn't leak to the upper soil. I have changed to soil for two weeks, the PH is 6.0 and KH 0-1 , I even need to add some baking soda to raise KH to 2.
As you said that "just laid one thin layer on the top.....", I guess you have just added a bag of 3L, it is not enough, add two more bags of 3L or even one bag of 9L. BTW, which type of soil are you using? Malaya (brown), Amazonia(black) or Africana(red)? I have asked the shopkeeper twice to confirm that the red soil (Africana) drops PH & KH most. It can drop the PH to 5.5 at the first few days and maintain the PH at around 6.0 with the injection of co2 after the tank is settled down. I have heard that someone used the brown soil(Malaya), it will maintain the PH at around 7.0-7.5.
Besides checking the PH, you should also check the KH. If KH is too high, PH will not drop much even you inject a lot of co2.