High alk.

Triggreef · Nov 24, 2015

Luckily in my fish only tank with barely any test corals in it. Not sure what would cause high alk. I don't test this system generally but I have been trying to get the nutrients down to make this a minimal reef with some easy corals. Anyway, I don't dose anything, but I have been dosing vodka for nutrient removal. Barely any water changes, actually went a couple years without a water change but I have done a few recently. So now that nutrients are in check, I began testing alk and CA and I get 14dkh and 400ca on red sea kits. I know the kit is good, it is the same kit I use on a normal basis for my other reef tank. Thoughts?

JAndersoncube · Nov 24, 2015

Do you use buffer on your top of water or when you change your water?

Triggreef · Nov 24, 2015

JAndersoncube said:
Do you use buffer on your top of water or when you change your water?

Not even a little bit.

Triggreef · Nov 24, 2015

If vodka doesn't have high alk, then I'm out of ideas.

JAndersoncube · Nov 24, 2015

Hmm, I'm sure someone with more knowledge will chime in.

cmcoker · Nov 24, 2015

Salinity is not high? That could inflate the numbers..

Triggreef · Nov 24, 2015

No it's about 1.024

Randy Holmes-Farley · Nov 25, 2015

What salt mix? Some can be close to 14 dKH. Have you measured yours?

Other sources of added alkalinity are anything in the tank made of cement (artificial rock, frag plug, etc.), tap water used for top off or to make water change water, and if nitrate levels are declining as bacteria use it (which produces alkalinity).

Vodka won't add any alkalinity.

Testing error is also a possibility.

Triggreef · Nov 25, 2015

Randy Holmes-Farley said:
and if nitrate levels are declining as bacteria use it (which produces alkalinity).

Could you expand on that a tad? I may have been overdosing as I got some big bacterial blooms, and bacteria on glass etc. Wasn't testing enough to see that no3 dropped to nothing and I failed to catch the point when I was supposed to cut dosage in half or whatever to the maintain dosage.

Also the salt is red sea regular, sometimes using the regular I/O to save a couple dollars since it was a non reef. Only talking about maybe 90g worth of water changes though.

And tap water coupld be the culprit, I use ro but the filters are super old and need to be changed. I use a separate ro unit for this tank v. my reef which is better kept. TDS reading on this one is 36 on the good water. I get TDS of zero on the unit I use for my reef.

Randy Holmes-Farley · Nov 25, 2015

Triggreef said:
Could you expand on that a tad? I may have been overdosing as I got some big bacterial blooms, and bacteria on glass etc. Wasn't testing enough to see that no3 dropped to nothing and I failed to catch the point when I was supposed to cut dosage in half or whatever to the maintain dosage.

Also the salt is red sea regular, sometimes using the regular I/O to save a couple dollars since it was a non reef. Only talking about maybe 90g worth of water changes though.

And tap water coupld be the culprit, I use ro but the filters are super old and need to be changed. I use a separate ro unit for this tank v. my reef which is better kept. TDS reading on this one is 36 on the good water. I get TDS of zero on the unit I use for my reef.

Normal IO is fine, IMO. I use it.

When nitrate is consumed by bacteria, they release alkalinity. Exactly the amount that is depleted when nitrate first forms from ammonia. So alk is only impacted by nitrate processes if it is accumulating or decreasing.

I'd bet on the tap water.

Triggreef · Jan 28, 2016

Randy Holmes-Farley said:
Normal IO is fine, IMO. I use it.

When nitrate is consumed by bacteria, they release alkalinity. Exactly the amount that is depleted when nitrate first forms from ammonia. So alk is only impacted by nitrate processes if it is accumulating or decreasing.

I'd bet on the tap water.

So since this message, I changed ro internals, have done several 30g water changes, brought vodka dosing way way down for a couple months. I believe I'm dosing about 16ml poor day now. No measurable no3. Po4 is still pretty high, been dosing LC to bring that down.

I am still maintaining 14dkh solid without dosing anything. I would think the water changes would have fixed this issue by now. I tested fresh made salt water and it only test at about 7.8 dkh.

Can't imagine what could be the issue bringing the dkh up so high. I'm also still accumulating big chunks of bacterial glob growth that I have to manually remove.

Meanwhile fish, shrooms, green nepthea and some zoas perfectly happy.

Triggreef · Jan 28, 2016

Anything I can do to slowly help the alk down? Aside from water changes?

Randy Holmes-Farley · Jan 28, 2016

What alk kit are you using?

You must be using nearly all of a syringe of titrant, if not more than one to get to 14 dKH?

Don't be offended, but some folks have been reading their syringes backwards, and the fact that IO is only giving 7.8 dLKH makes me wonder about this possibility.

Triggreef · Jan 28, 2016

Randy Holmes-Farley said:
What alk kit are you using?

You must be using nearly all of a syringe of titrant, if not more than one to get to 14 dKH?

Don't be offended, but some folks have been reading their syringes backwards, and the fact that IO is only giving 7.8 dLKH makes me wonder about this possibility.

For alk I use red sea. Also this salt mix was red sea and only mixed to about 1.022