So I've been running multiple low tech planted tanks for a while and have recently acquired a 29 gallon tank that I would like to turn into a blackwater tank.
So far though I'm finding that info on running a blackwater tank isn't readily available, and the info that is out there is really disjointed and there aren't any really good guides on what to do, where to get stuff, etc.
The tank is going to be sand substrate with (hopefully) oak leaves littered about on top with lots of locally found driftwood and really nothing else.
So I have a couple of questions. This is not going to be a planted tank, but I'm sure you folks can help me out.
1. I need a nice dark colored (preferably brown) sand substrate. In my other tanks, I've used both pool filter sand and play sand, but the PFS and play sand I've found tend to be fairly bright. They usually start as a pretty bright off white and fade to a still somewhat bright tan over time. I don't mind buying sand at a pet store, but if there's another better source for dark colored sand I'd like to know.
2. I've seen a couple of sources that say I absolutely NEED to use RO water to get the PH low. This is JUST for the fish that would typically inhabit a darkwater habitat right? The PH of my water isn't going to have any effect on the look of the tank or tannin leaching or anything, right?
Also, I can get one of these http://www.coralreefsupply.com/index.php?aquarium=ro_cl
RO units for fairly cheap locally (it's on clearance + I would have coupons/discount to get it for about $70). Is that RO unit worth it? Is there any reason I would regret buying that RO unit over some other one if I were to expand the use of the unit later on? (like trying a saltwater tank).
3. People keep talking about using peat in the filter. Will this alone be enough to give me the correct colored water?
4. How do I keep the water darkly colored when doing water changes? Add more peat to the filter?
Those are the main questions I have. If you guys have any other tips for me I would greatly appreciate them!