Zero GH with High PH and KH

PH/GH/RODI Question - Discus

PH 8.75
GH 0
KH 214 ppm
TDS 267

Location: Colorado, East of Denver

Link to water company report: https://rangeviewmetro.org/wp-conten...2023-CCR-6.pdf

I’m keeping some new 3”-4” discus and I want to lower my PH some with RODI but before I start this process I want to better understand how my GH from my tap (cold water) is testing nearly zero. For context, my new API GH tests turn a slight green after one drop.

Contingent on some testing, I’m planning to go with at least 50/50 RODI/Tap into my 55 gallon heated barrel for at least 24 hours and add seachem equilibrium to get the GH up but I want to have a better understanding why my GH reading is so low without a water softener and conformation I’m planning on tackling this the right way.

Any water pros out there today?

Thanks!

Hi,
I think I would try another GH kit. Your readings are really unusual.

If true.. I think your best bet is to use straight Ro and reconstitute with a commercial product. Normally I would suggest a tap water to Ro mix but your water as tested is really off.


Your KH is about 12 degrees hardness (214 ppm ÷17.9)
If you cut that in half with RO your kH will still be around 6 which will still buffer your water. If you want to lower your pH its probably best to use 100%RO.. You can try try using maybe10- 20% tap but with a GH of 0 I would be concerned traces are missing.
Al

I've lived in Moselle MS and outside Mobile AL. In both cases, my gH was 0. I have raised fish from a twinkle in the eye of his father to 8". I believe the fish get what they need from their food rather than from the water.

Thanks for the reply.

I posted this same question to Reddit and a person there thinks my water is softened from the water provider when considering the sodium levels on the water report I linked. I’ll call them to confirm this and might test the GH at my work so see if I get results (different water source).

I had a feeling I’d have to go with strait RO so I have seachem equilibrium and alkaline buffer on order. What levels for a grow out should I shoot for with the end goal to be a lowered PH?

I saw the DIY thread on remineralizing pure RO and may go that route in the future but for now the off the shelf product will work. Is there anything else I should be adding to get my levels back up besides the ones listed above or will those two cover all the bases?

Thank you!

I’ve heard that as well I just fell like my PH is quite high. I’ve read threads about discus in high PH but none have been as high as mine. Also, the sodium levels in my water have been concerning to others in other forums.

Quote:

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Originally Posted by LizStreithorst

I've lived in Moselle MS and outside Mobile AL. In both cases, my gH was 0. I have raised fish from a twinkle in the eye of his father to 8". I believe the fish get what they need from their food rather than from the water.

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If this were the case we could raise fish in distilled water and we can't.. Fish do take up minerals across the gills. .thats scientifically known. Im sure they can get minerals from their food as well but the whole reason most use RO tap water mixes or Ro Right type solutions is to put trace minerals in the water. .

You also have to remember that you do huge daily water changes... most hobbyists do not. Trace minerals are so small amount that its doubtful they even register on our test kits...
.

Seachem equilibrium is for planted tanks if you do a hardscape you can use Seachem Replenish liquid instead it mixes better. Careful with the alkaline buffer it will raise your PH quite a bit.

Quote:

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Originally Posted by bigkat503

Thanks for the reply.

I posted this same question to Reddit and a person there thinks my water is softened from the water provider when considering the sodium levels on the water report I linked. I’ll call them to confirm this and might test the GH at my work so see if I get results (different water source).

I had a feeling I’d have to go with strait RO so I have seachem equilibrium and alkaline buffer on order. What levels for a grow out should I shoot for with the end goal to be a lowered PH?

I saw the DIY thread on remineralizing pure RO and may go that route in the future but for now the off the shelf product will work. Is there anything else I should be adding to get my levels back up besides the ones listed above or will those two cover all the bases?

Thank you!

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We have members that have water in the pH of high 8s ..most domestics will do ok in it... I think if you get your pH into the 7 its fine for discus as grow outs.

Alot of water companies do buffer their water so it doesnt. Corrode pipes .

I agree that 0 tds water is not suitable for raising any sort of fish. When I used to use RO water I typically would remove the final deionization resin stage and I found that left enough minerals in the water to raise any type of software fish, including obligate blackwater wildcaught species. RO membranes are usually rated for 90% removal and I found that consistent with my experience - my tds from the tap is 90-120 and post RO it is around 10. However if you want absolute control over what's in your water then the DI resin stage is useful in removing that last bit from the water and leaving you with a blank slate to reconstitute to your liking.

Hello again,

So if I do go with the 100% R.O. route, what products do you recommend I should use to re mineralize and to what levels?

I have Seachem equilibrium for GH, what level should I shoot for?

For the KH, I'm thinking 5KH should allow for a decent buffer for a stable PH? Planning on using seachem alkaline buffer for this. I see this product recommends it to be used with the acid buffer but I don’t think I need to do considering I do weekly 50% water changes (usually 2x ~30% but let’s use worse case of 50% 1x). Am I missing anything with this thinking?

Looking for the best balance between stability and cost. Thanks again!

https://forum.simplydiscus.com/showt...92583-pH-GH-KH


You realy have a huge window of whats done.. moderately hard water and moderately buffered is a good goal.. whats more important is. Stability and frequent water changes.

Al

Ok so I have been testing the 100% RO, re mineralized to 3KH and 3GH, after 48 hours the PH is still 8.7/8 or so. TDS is around 120 if I rememberer correctly.

In your guys opinion, should I stop there or try to lower PH further with more extreme measures using muriatic acid? I tested in my 55 gallon drum (~50 gallons of RO water in it) with the acid and have it down to about PH of 7 (10 ml of acid) for 5-6 hours now. Will check it in the morning to see if it’s stable. The KH went form 3 to 2.

Question 1: why is my PH still so high? Curious more than anything.

Question 2: assuming the dosing remains consistent, are the long term downsides to the fish when using harsh chemicals (acid) to lower PH?

Question: is it worth it? If my PH was low low 8’s or high 7’s I’d just run with straight remineralized RO, with a 3 KH/GH. Overall, I just want what’s best for the fish long term.

Hi, I would not use muriatic acid.. I went that route when I first moved in to this house because I wanted a lower pH. Its a pain to titrate the right amount and your water pH will bounce . Any CO2 in the water makes it even harder to get to a stable result. It used to be something alot of people did but really has fallen out of use as. We realized stable pH is better

Your water pH is high still because its not being subjected to the. Nitrogen cycle and your starting pH was high.. Once in a fish tank with biological activities you will find the pH will drop lower as kH is consummed.

What are your values for straight RO water?

As it stands .. your water

Quote:

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Ok so I have been testing the 100% RO, re mineralized to 3KH and 3GH, after 48 hours the PH is still 8.7/8 or so. TDS is around 120 if I rememberer correctly.

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will be ok for domestic discus. As I mentioned before we have members with similar or higher pH.

Thought I replied but must not have posted.

Thanks for the advice, noted in the acid.

Out of my RO, TDS is 3-4 with 0 KH/GH. I didn’t not bother with a PH check on the pure RO.

I went and emptied out the acid water and filled up a bit of tap for a WC tomorrow.

Working on hard plumbing the RO to my house so should have the RO back up and running Tuesday to give the 100% RO remineralization a go.