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Balancing pH, KH, plant and fish requirements

1019 Views 9 Replies 4 Participants Last post by  Jeff B.
My first post, because I am having trouble finding specific advice for my situation.

I've an old 55gal. tank that I've had for years and am rejuvenating to make another attempt at a heavily planted aquarium. The problem is my (well) water parameters: the GH appears tolerable, c.70-80ppm; but pH is steady at 8.4, and the KH doesn't budge from c.220ppm.

Because most plants I've seen seem to require pH no more than 7.5 and KH up to 8, I added a new large piece of driftwood, and peat moss to one of the filters. It's only been a day so the pH hasn't changed, but the KH dropped to about 180-200ppm. I assume everything will drop a bit more and stabilize but don't have great hopes.

So, my questions: from most of what I've read here and elsewhere I assume that most fish can adapt, and it's best not to mess with the balance too much. My only survivors (one 10-12 year old Silver Hatchet and one same-aged Cory) have prospered. So, would a slow, "gentle" transfer of new fish into such a semi-drastic environment hurt them? I am well off the beaten path so it takes some time to get from a store (not to mention shipping them). Are softwater species like tetras more vulnerable?

And what are the consequences for plants? Are they as adaptable as the fish? If as I've read they can have a small impact on KH, will that compensate enough? I do not know what might have doomed our previous attempt at live plants- perhaps lighting, but if KH might've had an impact, do I have any recourse, or am I doomed to plastic?
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Can you see the "use before" or any other date on the KH and GH test kits? What brand are they? I can't see how you can have such a high KH without a high GH, since well water tends to have calcium/magnesium in it from the limestone aquifer, and that comes with carbonates so both the KH and the GH should be high. Is Pennsylvania water known to have these unusual parameters?
Thanks for the reply. Brand new API (liquid) test kit for both GH and KH, expiration date 5/2019.

And yes, somewhat surprised as well, but I've tested it multiple times. Aside from interpreting the vague instructions (add drops until it turns green? Is that deep forest green, or 1st bud of spring green?) the results have been consistent for a month. Before that I did not even test for hardness until I started reading up, and realized this was new ground (water.)

Not sure whether all of NW PA is alike, but I work in a former limestone mine, so I assume there might be some under the house, too. Our water has to run through a whole house softener and filter for the iron (I could open a smithy from what the filter dredges out.) So perhaps the water filter is keeping the GH down, but somehow not touching the KH? We do have some sort of white buildup (calcium, I assume), bad enough to have had to replace the canopy twice now...
If I recall correctly a water softener will take out the gh and leave the kh so that would be your answer.
Thanks. So, my original questions, then: will this set of odd parameters (hopefully mitigated a bit with the peat and driftwood) be tolerable for new softwater-preferring fish?

And any concerns with plant growth in this situation? Is such high KH tolerable for live plants?

If further mitigation is needed, what options are there besides RO? Not sure that's within the budget right now...
Can you test the water before it gets to the softener? If it's "acceptable" just use that.
When a water softener removes the calcium from the water it replaces the calcium with sodium or potassium. Neither is really good in the amounts involved here. But, you could use a RO/DI system, a portable one, to make the water usable for an aquarium. You would have to add back some GH builder before using it though. It isn't an easy problem to solve cheaply.
Thanks again. So the Big questions then, are will this water the way it is now 1. make it hard for softwater fish to adapt, and 2., should I expect problems plants?

RO isn't an option right now. I've read that most bottled water is RO processed. If this is true, if I have to I can experiment- if it's necessary for the fish and plants.

But if it's not necessary I'd rather not since I'd have to mess around with it every water change.
There are fish that live in water that is brackish, there are fish that live in water that is very hard, so you should be able to find a selection of fish that can live in your un softened well water.

Plants might be a bigger problem. I haven't done the research to be sure, but I think there are at least a few plants that do well in water like yours, vals, for example. I think, in your situation I would research that, then try a few of those plants to see how they do, leaving the fish issue for later. Once you find a set of plants that like your water, you should have had enough time to settle on some fish species that should also do well, so you would be ready to start adding fish.
Thanks again. I've found just a few that specify that they tolerate hard water (Anacharis) and several others that say the plants are flexible, i.e., the parameters don't matter very much (Java fern, Wisteria). We'll see what happens from here.
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