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Bore Well / RO Water and Rocks that raise PH

2364 Views 5 Replies 4 Participants Last post by  lochaber
Hi Everyone,
I am new to aquarium and will be setting up my first planted tank soon.
Tank – 29G (100L)
Water – I can either use Bore Well Water (PH around 8.2) or RO water (PH 6.4)
I bought few ADA Rocks which I have cleaned and tested with Vinigar. Even though I could not see any visible Fizz, I could hear a faint ZZZZZ sound. So I have soaked these rocks in a bucket of Bore well water for the past 3 days. I tested PH again after 50 hours and the PH now shows as 8.6.
Will I be OK to start with Bore well water? Is there any items that I can add to lower PH. I want to keep this as low tech as possible. I am not fond of dosing chemical on a regular basis to treat water if possible. I want to maintain the tank as self-sustaining as possible with regular water change / clean / minimum ferts as needed.
Now following are my questions:
Which water to use? Start with RO water and top up RO water only? Hoping that the Rock will anyway going to raise the PH.
Should I ditch the Rock and go for something else altogether?
Any suggestions in this regard will be great. Thanks in advance.

I will try posting the Rock's picture tomorrow...
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I would suggest your bore well water is fine to use but I wouldn't add the rocks if you believe they will effect the PH. What seems to be important is a constant PH as opposed to worrying about the actual PH and a reading of 8.6 is not bad at all. If those rocks are limestone based then your PH is going to fluctuate from one WC to the next.
Here is what Tom Barr has to say about tap water and hardness of water;

Using tap water

Tap water is cheap and water changes take less time than the testing (salt water is the exception perhaps, salt mixes cost a fair amount money). Water changes also cost less than test kits/testing and are more fool proof method of estimating the nutrient levels in your planted tank when dealing with NO3, Fe and PO4. It's also simpler and requires less knowledge of chemistry and testing against known standards. Plants are most often starved of nutrients and inaccurate test kits are largely responsible. Many people feel tap is unsuitable for plants, this is simply not true. Old myths still abound claiming excess PO4 in tap water causes algae, this has clearly been shown by many hobbyist to be patently false. The tap water has nutrients in it, then you do not have to dose these nearly as much, this is actually a good thing! Why take something out and then add it back again?

Have hard water?

Great, you do not have to add any baking soda and GH builder to your tank. Adding enough GH to bring the levels to 3-5 GH degrees will address higher light tank needs over a week's time. You can use SeaChem Equilibrium for this or a mix of CaCl2 (or CaSO4 although it is not as easy to dissolve into water) and MgSO4 at a 4:1 ratio to increase GH. You can add this without knowing what your GH is by adding 1 degree's worth after a weekly water change (or slightly less with less frequent water changes)

Plants prefer soft water? Not so, neither myself or other experience aquarist have found plants that are soft water dependent, although there may be a few exceptions out perhaps 300 species, it is safe to say that plants prefer harder water and there is research to show this is true, (Bowes 1985), (T. Barr, C. Christianson observations of clear hard water springs in Florida, USA and in Brazil). A few plants, about 5 or 6 or so species do seem to prefer softer water, but this is due to KH, GH seems to have little bearing as long as there is enough Ca and Mg. So the GH can be dosed a little higher if in doubt or if you want to check to see if that is causing an issue or not.
KH on the other hand does seem to influence these specific plants(most are not affected) to about 5-6 degrees. There is really no limit on how low the KH can be for good plant health, but it can make CO2 measurements trickier. There is a way around that though. Still, any plant can be grown at a KH of 5 and a GH of 5-10, or less. This would not be considered "soft" water, actually it would be ideal. Thus unless you desire to grow a few eclectic species, there is no need for RO, nor DI, carbon filtration of the tap water, but doing so will do no harm to the plants as long as there is enough GH for the plants and KH to determine CO2.
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Water and rocks that may change the water are often discussed but I feel there are points often missed. One is how the rock may change the water if it is a local rock. Your well water is likely to be running throught rock most of the time. If not it is running through dirt and will not be quite as clean looking. So the question may be, what change is expected if the water is in the rock or if the rock is in the water? It is true that the surface rock may be a different type than the underground water but is it that much different that it is likely to be trouble? When you have high PH and hard water, I find adding many other things like rocks or wood has little effect. If you had soft acidic water and added a lot of limestone rocks, the change might be dramatic but that is not your situation. The acid test may tell you the rock is alkaline. Add acid to alkaline and you expect fizzing. Add alkaline rocks to alkaline water like yours and there may not be much change. I would go with the rocks and water you have and not worry until you reach some point where you find a fish or plant you really, really want is not doing well. May never happen or ten years from now you may have to change.
The change in testing PH may come about the same when you just let the water set and gas off.
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A lot of the rocks used in those ADA/Amano style set ups are just heavily weathered limestone. (which is what the fizz test is checking for - the presence of carbonates.)

People do have successful tanks with them, but it's worth noting that a lot of those rocks aren't inert.
Hi Steve,

Thanks for the post and it is a great read. This has answered some of my nagging doubts. I think I will return the rocks and get something else. I am planning to carry a bottle of Vinigar this time to the shop. I may even consider DW for now along with few smaller inert rocks. Thanks again for sharing.

Hi PlantedRich,

Add acid to alkaline and you expect fizzing. Add alkaline rocks to alkaline water like yours and there may not be much change.
Very good point. I never considered that. I do not have any experience with FW Planted Tanks and I am a bit scared of screwing up. I may probably take a safer approach and select few inert rocks to start with. It is a big relief though that I can still use the Bore Well water even though the PH is high.

Hi Lochaber,
Thanks for the input. Yah. But I thought these ADA rocks were inert. I simply assumed it never even checked with the shop owner. The rocks look similar to those shown below: (The image is not mine).

Few more question:

Since at my place I get regular supply of RO water cheap and I also have a smaller home RO system (enough for regular water changes of up to 7 or 8 G daily), Is there any advantage in going RO route?

Is there any good for Planted tanks to have under gravel trays? Does it reduce the possibility of having the Anaerobic Air pockets?

What are the must have Ferts / Chems that I should buy by the time I fill the tank up with Plants?
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Yeah, those rocks in the pic are a limestone.

It's really hard for me to explain it well, but limestones tend to have a very distinctive weathering pattern. cracks widen, smooth out, you get little scoop-like pockets with pointed peaks in between them, etc. I haven't seen anything else that weathers quite the same way that limestone does.

It does make for interesting looking rocks, which (I assume...) is why they are often used in the really high-end scapes. Also, the people who do those scapes typically do a lot of maintenance, so frequent water changes and what not would help control the water parameters.
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