need advice on RO DI vs peat?

[kimura]

the water in my loach tank is fairly soft although i dont often check it. the ph is usually around 7.2-7.3 and ive been contemplating either using a RO unit for my water changes or adding some fluval peat. i want whats best for my loaches but i dont want the water parameters to swing because i know this is often worse than something stable. long term cost is also a factor in the equation. i am open to any advice or first hand info anyone is willing to share. thank you.

[kimura]

so nobody has ever heard of RO or peat? thats interesting........

[Martin Thoene]

There's a few people here who use RO. I guess someone will respond.

No experience with it myself, so can't comment.

Martin.

[TammyLiz]

Of course most people here have probably heard of it. But you were asking for first hand experience. That I don't have because I already have soft water. I can tell you what I know, and that is pure R/O is not a good idea since it does not have adequate minerals. A good way to use it is to mix it with your tap water, and play around with the ratio until you get the right mix. There are a lot of people who do this. It sounds like your water, if stabilizing around 7.2-7.3, probably would need mostly tap. Going off of that a 1 to 2 ratio of RO to tap sounds about right. To have a better guess, check your KH. You'll want a test kit for that if you're messing around with things. I actually buffer my KH up, because my pH crashes if I don't.

If you use enough peat to change water chemistry you'll end up with tea stained water from the tannins. I personally don't mind it as I have some driftwood in one tank that leaches tannins strongly and think it looks kind of nice. Very natural. Some people hate it, though, because the water isn't as clear.

Of course this isn't first hand experience from me, but I read a lot of the experience of others. Maybe too much. I should go get something done.

[chefkeith]

pH is by far the most misunderstood water parameter in the aquarium hobby.
Hourly/Daily pH fluctuations are mostly from changes in CO2 content. This change in pH, small or large, is in no way harmful to fish. Tannic acid, peat, and driftwood is all the same thing. These will reduce pH also, but this change, small or large, is in no way harmful to fish. pH is also changed by bi-carbonate alkalinity (kH). Changing this rapidly can harm your fish.

CO2/pH changes occur in every aquarium system. A cycled filter converts oxygen to CO2 in the nitrification process. Fish change O2 to CO2 when they respire, and when the lights are turned off, plants/algae convert O2 to CO2 also. In some systems, like mine, all this CO2 adds up to large pH changes that is not harmful to fish. pH meters are used by planted tank owners as a way to monitor CO2 levels. High levels of CO2 can be harmful to fish.

In otherwords, most important thing is keep your kH steady. Changing your pH makes little difference to your fish.