high and unstable ph problem

[eriond]

Hi all,
I faced a high ph problem when cycling a new tank (fishless) with 20% old water from my existing tank. apparently the tank seems stable with no trace of amonia or nitrite. in fact tank water is brownish from the bogwoods so i assume soft water. i tried water change 30% last weekend and placed in 4 pcs of ketapang leaves but ph still register high. before light on ph 7.6, during light on 7.8 to 8.0, after light off 7.6 during cycling, i have thrown in some rotting tubifex in small amount, some fish food to rot somewhere around wk 1 n 2. i have been checking ph since last week and it is stubbornly as mentioned.anyone has any idea how i can lower and stable ph without co2 ? i hope to achieve ph 6.8
pls advise, thanks.

Beginners Info Sheet
++++++++++++++++++

Tank Dimensions (LxWxH): 120x45x45 (240l)
Lighting Intensity(No of Watts) : 4 x 36w
Type of Lighting (FL/PL/MH) : PL
No. of Hours your light is on: 6 and gradual to 9 within 30 days spread
CO2 Injection Rate (bps) : NA yet
Type of CO2 (DIY/Liquid/Tank) : NA yet
Method of Injection (e.g. Diffusor/Reactor): NA yet
Substrate Used : Taiwan brand forgot the name
How Thick is your base fert : 1 inch
How thick is your gravel : 2 inch
Liquid Fertilizers Used : LushGro Aqua (started after 20 days)
Frequency of fertilization : weekly
Tank Temperature : 26.5C
Type of Filter (overhead/internal/canister) : internal
Filter media used : black sponge
How long has your tank been set up : 32 days


Chemical Properties (Fill what you can)
---------------------------------------

Carbonate Hardness (kh): 6 (was 4 increase to 6 via CaCo3 tablet)
Total Hardness (gH): not sure, Gh test kit spoiled
PH : 7.8
NH4 (ppm): 0
NO2 (ppm): 0
NO3 (ppm): suspected but no idea
PO4 (ppm): suspected but no idea
Fe (ppm): 1.18 (weekly basis)

Bioload (Your Fish and Plants)
------------------------------

<State what fishes and plants you have to the best of your ability>
No fish yet.
Plants - e.tenellus, e.quadricostatus, a.nana, alternanthera ficoidea, v.spiralis, nymphaea red lotus and bogwoods (quite a few pieces)

Describe your problem : High ph and not able to lower and stable at all.

<problem description. If you have picture which could help then please post them>

[vinz]

[quote:8a13a93530="eriond"]...

CO2 Injection Rate (bps) : NA yet
...
Carbonate Hardness (kh): 6 (was 4 increase to 6 via CaCo3 tablet)

...[/quote:8a13a93530]

There's the cause of your problems. Are you blindly adding KH without knowing why people add KH to planted tanks?

Briefly, if you raise your KH, your pH will rise too. KH is used in planted tanks to buffer (or counter) the drop in pH from CO2 injection.

Bad newbie! Bad! Bad! :P :P :P Now, go read http://www.csd.net/~cgadd/aqua/art_plant_co2chart.htm.

[vinz]

Anyway, your light level is fairly high and you're dosing liquid fert, yet you're not injecting CO2. That's an algae bomb waiting to explode.

[eriond]

[quote:36261375="vinz"][quote:36261375="eriond"]...

CO2 Injection Rate (bps) : NA yet
...
Carbonate Hardness (kh): 6 (was 4 increase to 6 via CaCo3 tablet)

...[/quote:36261375]

There's the cause of your problems. Are you blindly adding KH without knowing why people add KH to planted tanks?

Briefly, if you raise your KH, your pH will rise too. KH is used in planted tanks to buffer (or counter) the drop in pH from CO2 injection.

Bad newbie! Bad! Bad! :P :P :P Now, go read http://www.csd.net/~cgadd/aqua/art_plant_co2chart.htm.[/quote:36261375]

ok, ok, ok, i knew i was wrong the moment i did it as i was thinking of forcing an alteration...oh well nevermind. anyway, how can i lower my ph now? do i need to lower kh too ? i don't really wish to have co2 in this tank and i know my tap water has about 3ppm of co2 (kh4 ph7.6) so what can i do to achieve lower ph ?

[augi_ow]

by right.. you are suppose to lower your ph by injecting CO2>> your kh must be around 3-4
but there are products on the market which lowers your ph.. very common product>>> can find in any LFS

[augi_ow]

got something to ask you....
how you keep your temp at 26.5 with 4 x 36W PL lights

[eriond]

[quote:2f85376d71="augi_ow"]by right.. you are suppose to lower your ph by injecting CO2>> your kh must be around 3-4
but there are products on the market which lowers your ph.. very common product>>> can find in any LFS[/quote:2f85376d71]

no offense bro, i know there are many products to the solution but this are temp and are unlikely to stabilise my ph in the long run.

[budak]

haha, don't mind vinz, he's often cranky when it comes to newbies


With a non-CO2 tank, you need not bother with liquid fert at all... ditto the CaCO3 tablets. Just rely on your base fert. Only thing is to keep changing water until the KH is brought sufficiently low (3-4) such as that buffering capacity is minimised.

For lighting, keep it if you like, but except for the Alteranthera, your plants should be fine with just 36Wx2. But why are you using just an internal filter for a 4 ft tank, unless your bioload is very very low?

If you are serious about non-CO2 tanks, Diana Walstad's book (do a search) is a must-read. Suffice to say, the regime goes like this: don't dose fert, minimise water changes (every few months), don't overcrowd, overfeed slightly and keep lighting moderate. It works.

[eriond]

hint hint, looking to get a good bargain of an ext cannister so boh pian stuck with an int filter till i get one. as for lighting n liquid fert, well i was a little worry about the nymphaeas. as for bioload, still haven't decide who's going to be in yet. maybe current tetras n cories from other tanks. and as for co2, well i did not want to expense that further just trying to recycle what i have at present, that's all.
anyway, thanks for all the helpful bros around, i m not offended at all but appreciative. this is a good informative forum, actually been coming as a guest for quite a while oredi. so pai sei, only decide to join as member recently

[bclee]

First of all, we cannot expect pH to stay consistant at one value. Throughout the day as temperature, conditions changes, pH level changes. It is normal for pH to fluctuate within ± 0.2~0.5.

pH is tied to KH, CO2 and other buffers. If you would like to lower pH without using CO2 injection, the only way is to reduce KH or add buffers.

In reducing KH, you can:
1. Water change using tap water. But the lowest KH level you can go with this method is to the level of the KH in your tap. With the typical KH in our taps, the pH at equilibrium will definitely be >7 (around pH 8 ).

2. Use RO water. RO water has KH close to 0. But investing in a RO system will cost more than a CO2 system.

3. Use peat. Most of the peat will stain the water brownish.

Alternatively, you can add buffers to you water. But personally, I do not find any purpose for using that.

But before all this, you must realise what is the purpose of lowering the pH. Although there is so-called "ideal" pH for certain plants or fishes, most of them can tolerate a wide range of pH. IMO, pH is never a critical parameter for me other then determining the right amount of CO2 for my plants.

BC

[hobbit6003]

I think newbie or not, one must have an understanding about why some things are done the way they are, and not just blindly doing them, as in this case, lowering pH.

The planted tank people uses the pH as an indicator to the amount of CO2 injected, and buffering it with kH to stabilise the pH so as not to let it plunge, to prevent a pH crash.. It is a simple acid-base relationship.

Hobbysists therefore use the pH-kH relationship as an inference to the concentration of dissolved CO2 in the water, and then tweak these values accordingly to achieve the desired dissolved CO2 concentration.

The above works on the assumption that the contribution from other sources to the acidity of the water is negligent or insignificant.

So, assuming that COs is about the only significant contributor to H+ ions (acidity) to your water column, your apparently high pH with a kH of 6, will only yield you 3ppm of CO2 technically speaking.

Therefore, don't just lower pH for the sake of lowering it, you must find out why you're doing it.

As for stabilising pH in there, you have to tweak and adjust your CO2 input and injection duration, or alternatively, invest in a expensive pH controller. A diurnal fluctuation of 0.2 should be alright.

Also, you cannot assume that your nitrogenous waste 'seems' stable, it is better to invest in some simple test kits, and able to quantify them. Granted that most commercially afforadble test kits are not extremely accurate to the T, but they'd offer you a pretty reasonable inference.

Please don't take this as an offence, or as an anti-newbiw comment, for such things can happen to even the most experienced hobbysists too.

Cheers,

Kenny

[eriond]

Thanks to all !
Already did water change, will continue to do it till kh lowered. As for peat I have tried much earlier without success. anyway will stick with the ketapang leaves for now.

[eriond]

[quote:add4d6e4de="augi_ow"]got something to ask you....
how you keep your temp at 26.5 with 4 x 36W PL lights[/quote:add4d6e4de]

Well I have a spare fan blowing (only in the day) and it has been rather cool lately. The tank is also in my study room which is strangely the coolest place in my house. Even I m puzzled, coz my other tanks outside living room with fan blowing only achieve 27 degrees. Seems like a good place for plant tank though.

[hobbit6003]

[quote:97bc379ea4="eriond"]Thanks to all !
Already did water change, will continue to do it till kh lowered. As for peat I have tried much earlier without success. anyway will stick with the ketapang leaves for now. [/quote:97bc379ea4]

Hi eroind,

Well, peat and ketapang leaves will not help increase your CO2 level, that's for sure.

CO2 is what you need in there to make your plant thrive.

Cheers,

Kenny

[vinz]

Maybe your thermometer isn't well calibrated, which could be the case with cheap hobby-grade ones. But, it's possible to get that temp in the current weather just using fans, if the room is well ventilated or very insulated from the outside heat.

If you going to do without CO2, then I suggest you turn off half 1 or 2 of the bulbs and stop dosing liquid fert. Your nymphae should be rooted, so use substrate ferts sticks/tabs/etc to provide them the extra nutrients they would need. You'll need to review your plants too... some may not do well without the CO2 and lights. Some just grow slower and smaller.

The rest Budak mentioned.

p.s. hope you noticed the smiley's in my previous reply. :P

[hobbit6003]

Oops,

Didn't notice this is tank w/o CO2.

Yup, Diana's book is worth more than a read on mataining a low tech tank.

But please do not expect a luxuriant foliage in a short time, that's it.

Cheers,

Kenny

[eriond]

Thanks vinz,
oredi done all since ur first reply. nothing wrong with my thermometer, it is really cooler, room thermometer confirmed it. and REALLY, i am not the least offended, angry or what REALLY REALLY .
just joking, anyway I have been pondering the problem much much earlier, just got impatiently confused, hence the raising KH. I knew I was wrong n sure kena tarok by u guys but still I put in the fact honestly (bravely) so that I can get a good valid opinions from u guys. I have been quietly reading this forum for a while and found most of u guys helpful so I thot I share to get better ideas. Of which I definitely have learn a few. don't worry about me I know what to do. Now go bug another poor victim . just joking

[juggler]

[quote:6748e3848c="eriond"]Carbonate Hardness (kh): 6 (was 4 increase to 6 via CaCo3 tablet)
Total Hardness (gH): not sure, Gh test kit spoiled
PH : 7.8
[/quote:6748e3848c]

Your kH of 4: Did you add baking soda or do you have any corals or alkaline stones in your tank? If so, that may explain your higher pH. Our tap water kH is about 0~2 only I tested so far.

[eriond]

[quote:f429595e="juggler"][quote:f429595e="eriond"]Carbonate Hardness (kh): 6 (was 4 increase to 6 via CaCo3 tablet)
Total Hardness (gH): not sure, Gh test kit spoiled
PH : 7.8
[/quote:f429595e]

Your kH of 4: Did you add baking soda or do you have any corals or alkaline stones in your tank? If so, that may explain your higher pH. Our tap water kH is about 0~2 only I tested so far.[/quote:f429595e]

staying in hougang, tap water kh3-4 ph7.6 tested a few times oredi. cannot run one. anyone in hougang area tested their water ?

[juggler]

[quote:4000bea49c="eriond"][quote:4000bea49c="juggler"][quote:4000bea49c="eriond"]Carbonate Hardness (kh): 6 (was 4 increase to 6 via CaCo3 tablet)
Total Hardness (gH): not sure, Gh test kit spoiled
PH : 7.8
[/quote:4000bea49c]

Your kH of 4: Did you add baking soda or do you have any corals or alkaline stones in your tank? If so, that may explain your higher pH. Our tap water kH is about 0~2 only I tested so far.[/quote:4000bea49c]

staying in hougang, tap water kh3-4 ph7.6 tested a few times oredi. cannot run one. anyone in hougang area tested their water ?[/quote:4000bea49c]

Really? Looks like you keep on your Ketapang leaf treatment and see how. It does help reduce pH. But if your fish are not complaining, there's really no harm. My tanks are also at least 7 pH or more because I put in some coral chips in the filter.