High alk

[Psychotic Madman]

Hi all, hoping for some help here. Been a member on here for a couple of years now, browsing and researching, but i am stumped to find answers to my problem. My original tank, Aquaone nano120 (120ltrs) was getting a little tired, so, on the 10 may this year, i got delivered my new tank, Neptunian cube p60 (247 ltrs total volume). Only new thing in this tank was extra water and a small amount of new rock, seeded in my old sump. Changeover took approx 6 hours with all rock and sand being stored in large tube with heaters and wavemakers. Tested every day for the 1st week and all perameters were within the accepted range and stable. Only dosing AFR. Unfortunately about 3 weeks int this new tank i spilled some concentrated copepods in, not too much, just a little that was left in the bottle, probably about 5 ml. Next day i had very cloudy water and a few dead fish and corals. Did a massive water change approx 100 ltrs. \\\\\\\this "bloom" cleared up and i thought i had sorted it with the water changes. Tested water and alk and calcium were off the scale, nitrate had dropped form 10 to 2. Immediately stopped dosing and kept testing. My perams are still not right and i am wondering what is the best way to lower alk and calc and raise nitrates. I feed 2/3 times a day, early feeds are granules, last feed is frozen(variety, different every day) with live brine shrimp (1 bag). I also put 10 bags of live copepods in the sump each week. No skimmer, running a ref with cheato (small amount), Put about 2 m of phyto in for the corals each day too. Corals are LPS, Softies, and a few small zoas, all seem to be thriving especially my Euphyllia and Blastos. BTA is also looking very healthy. New lights, changed from Nicrew 100 (good little light) to Evergrow 5060 (much better light), not run at over 60%. I am suffering with quite a bit of algae on the glass which is scraped of every 2/3 days.
Fish are
2 clowns
3 queen anthias
8 blue green chromis
1 firefish
i bangai cardinal
1 possum wrasse
2 very small bluestar damsels
1 hawkfish

All fish are less than 2 inches.
I have stopped doing water changes and top up with ro with no buffer. My current perams are as follows
Nitrate 2
PH 7.5/8
Phos 0.03
Alk 15.0
Mag 1400
Calcium 500
Sal 1.025
My temperature is controlled through Inkbird controller and site at 24.6.
I think i have given as much info as is needed, but as i am still learning about this hobby, i may have missed something out, if so, please let me know and i will post up.
Thankyou for any help anyone can giveme as this is really getting to me, i just want my fish and corals to be happy .

 

[Formulator]

Wow that is pretty high. It is important to lower the alk slowly. No more than 0.5 dKH lower per day. I suggest to start doing small daily water changes with a lower Alk salt mix. I think tropic marin pro is about 7.0 dKH as an option.

Or you can use muriatic acid (hydrochloric acid) to lower the alkalinity of water you make with your existing salt mix. That will also lower the pH though, so I recommend aerating it for a day or two to bring pH back up.

As a last resort you can add the acid directly to the tank, but the pH lowering effect can be extreme making this option more dangerous.

High calcium won’t hurt anything. The water changes will help, and you can just let it fall the rest of the way on its own over time.

 

[Randy Holmes-Farley]

Try your alk kit on some new salt water. Are you using ro/di?

 

[Psychotic Madman]

Thankyou for the quick replies. I buy ready mixed saltwater from my lfs, i think they use a TMC mix, which is suppoesd to be very good, always used it with no issues before.I am not really confident enough to add more chemicals to an already unbalanced tank. Small water changes seems to be a better option to me. I will try doing 5 ltr changes each day for a week and see how things are then. Forgot to add, my kits are all Salifert. All my kits were replaces a month ago, so are not past their best. I have tested the water before it goes in the tank and it is usually stable at around 9. I may try some lower alk salt to mix my own if there is no change. Yes always use rodi water for top ups. Once again, thankyou for your ideas on how to solve this problem. I will keep you ainformed of my progress.

 

[Psychotic Madman]

Update, Just got some fresh saltwater from the lfs, ALK is supposed to be between 7-8 according to the salt mix label. Tested when i got home and straight from the tub i got 10. So not a faulty test kit, well in date (08/28). Will be doing daily water changes for the rest of the week and will test every day just before changes.

 

[Miami Reef]

Update, Just got some fresh saltwater from the lfs, ALK is supposed to be between 7-8 according to the salt mix label. Tested when i got home and straight from the tub i got 10.

How is the kit not faulty if its supposed to test 7-8DKH, but it’s actually testing it at 10dKH?

That means that your alkalinity might not be as high as you think. Try a different kit.

What test kit are you using?

 

[Psychotic Madman]

Well its not testing double what it is supposed to be, so its not the kit that is too far out. I have already stated that i use Salifert kits. I will be taking some water to the lfs tomorrow for testing, see what it is there.

 

[Formulator]

I think my reef crystals are supposed to mix around 12-13 dKH and have always landed around 9-9.5, so I wouldn’t necessarily say the test is bad.

The salifert test (really all colorimetric titrations) can be somewhat variable based on what you are calling the endpoint. i.e. start of color change vs complete, etc. There is some good discussion in this thread if you are interested:
Thread 'Color Change in Salifert Test Kits...how do I know when it's done?'
https://www.reef2reef.com/threads/c...test-kits-how-do-i-know-when-its-done.376231/

Great idea to have your LFS do a confirmatory test as well.

 

[Psychotic Madman]

Very interesting read. That thought never crossed my mind. I usually comper when the colour has changed completely. I will try again when i get back home. Maybe its my process that is broken and not the kit. Thanks for that.

 

[DanyL]

Just in case - make sure the equipment you test your salinity with is properly calibrated.

 

[Psychotic Madman]

Always calibrated prior to use

 

[Psychotic Madman]

Took some water to lfs today, he gets the same result as me. Water changes for at least 2 weeks coming up.

 

[Psychotic Madman]

Well, after a week of small waterchanges( 25 ltrs over 5 days) and topping up with 5 ltrs ro, there is no change whatsoever.

 

[Garf]

and top up with ro with no buffer

This part implies you have been adding adding a buffer, but not now? If so, what buffer?

 

[Garf]

Always calibrated prior to use

With RO, or a 35ppt solution? There's a link to Randy's DIY calibration solution in my sig if interested.

 

[Psychotic Madman]

Was just a buffer that the lfs added if asked for. I have been using this for 2 years with no adverse reactions. Stopped using as i did not want to add any further elements to my tank till my alk problem is sorted out.

 

[DanyL]

A buffer is essentially an alkalinity supplement. There’s your problem.

5l water change per day for 5 days in a 125l system would not have a big enough effect on your water chemistry to notice a significant decline in alkalinity, unless using significantly lower Alk salt.

 

[Psychotic Madman]

Not a 125ltr set up,and if you read the whole post you will see that i stopped using any buffer as soon as i noticed my elevated levels of alk. Also, after 2+ years of using it, i dont think my levels would almost double overnight. Salinity checker is cilibrated with Continuum calibration fluid.

 

[Garf]

topping up with 5 ltrs ro

Do you make the RODI ? Can you check the TDS if it's bought (or an alkalinity test would do it).

 

[Randy Holmes-Farley]

Assuming the alk is high, it was suggested earlier in this thread how to lower it using acid, such as muriatic acid or sodium bisulfate to treat new salt water to give very low alk.

Sodium Bisulfate to Reduce Alkalinity in New Salt Water or in Display Tanks

I just want to record these calculations in their own thread to refer back to in other threads. When alkalinity is too high in new salt water or in a display tank, acid can be used to lower the alkalinity. You can easily use muriatic acid (hydrochloric acid), or sodium bifulfate (e.g...

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