water gone mad

[suedaunter]

can anyone help me please. I can't understand whats going on with my aquarium water!, I have a ph of 7.5, but KH is 1*dh and GH is 3, I use a master testkit and ph probe which give the same results. I keep discus with bare-bottom tanks running into 1 sump, the sump has alfagrog, sponges and floss. I do waterchanges with RO and tap water. In my RO storage bin the PH is 6.6 so I can't understand where the alkilinity is coming from - any ideas?

[Northernguy]

It could be rocks,wood,type of substrate used.Cannot tell without a description of the tank or a pic or two.

[suedaunter]

Hi, thanks for your reply, I don't know how to get pics on here yet, all tanks are bare-bottomed except one I keep for neons which has the black gravel, I tested it with vinegar and it did'nt fizz so I assumed it was ok, in the same tank I have a large mat of java moss, water millfoil, amazon sword and a small piece of bogwood. I have small pieces of slate with white plastic pipe siliconed to it in the other discus tanks as breeding 'cones'. I have 3 heaters in total (500, 300 and 200 watts). 1 pump and the ph and orp probes in the sump [with alfagrog, sponges and floss). I filter the ro & tapwater bin through peat using an external filter. Hope this helps towards a diagnoses, half of the eggs that were laid Saturday have now turned white (I can see movement in the remaining ones), so would I be right in thinking this would be due to the ph?

[Cliff]

I'm not too sure I am correctly understanding what you are saying in the last part of your post.

Are you using RO water, or tap water, or both ?

[suedaunter]

yea, I use RO water and 2 buckets of tapwater which I mix and get up to temperature in a plastic bin, and I use an external filter containing just peat [and a bit of floss to stop any particles], with both in and out pipes into the bin so it's circulating, I used to use it in the sump but find this method a lot cleaner. hope this helps.