Need help with acclimating tank to lower alkalinity from a super high one

[kiran]

Hey guys,

So I ordered a 7-stage RODI unit and bought the Red Sea Coral Pro salt mix. My alkalinity right now is crazy high (it's been reading 20+ on multiple tests and from what Ive heard having a dkh in that range isn't supposed to be possible). I'm going to be lowering my dkh slowly to around 11dkh and was wondering how I should go about it so I dont shock the tank or make anything stressed severely.

I was thinking maybe 20% water changes every couple days? This is me making a super uneducated guess so any advice is welcome.

Thanks!

 

[ScottB]

Hey guys,

So I ordered a 7-stage RODI unit and bought the Red Sea Coral Pro salt mix. My alkalinity right now is crazy high (it's been reading 20+ on multiple tests and from what Ive heard having a dkh in that range isn't supposed to be possible). I'm going to be lowering my dkh slowly to around 11dkh and was wondering how I should go about it so I dont shock the tank or make anything stressed severely.

I was thinking maybe 20% water changes every couple days? This is me making a super uneducated guess so any advice is welcome.

Thanks!

Unless you got a really bad batch, that cannot really be right. The stuff mixes to 11. Maybe recalibrate your refractometer?

 

[kiran]

Unless you got a really bad batch, that cannot really be right. The stuff mixes to 11. Maybe recalibrate your refractometer?

I did 4 tests with an API and Hanna alkalinity meter and both reported over 20 dkh. 2 tests with the API kit and both times it stopped at 21dkh. The Hanna I also did twice and both reported 20+. I reread the instructions over 20 times and I can promise that I followed them exactly.

I get my water from a local LFS and I don't know what they're doing to the water but I tested it right out of the jug an hour after receiving it and it read high.

That's the reason I decided to get a RODI system and my own salt.

EDIT: I just realized the way I worded it made it sound like I've already used the RODI system and the Red Sea salt. I haven't used it yet the water I tested was from my local fish store. The RODI + Red Sea is what I'm planning on using and bringing down my current dkh down to the red sea recommended dkh.

 

[ScottB]

If I have to do a HUGE water change, I have to knock down my IORC that also mixes at 11, while I run 7.5-8.

You have to gas off all the CO2 it generates though for a couple hours.

 

[kiran]

If I have to do a HUGE water change, I have to knock down my IORC that also mixes at 11, while I run 7.5-8.

You have to gas off all the CO2 it generates though for a couple hours.

I just realized the way I worded it made it sound like I've already used the RODI system and the Red Sea salt. I haven't used it yet the water I tested was from my local fish store. The RODI + Red Sea is what I'm planning on using and bringing down my current dkh down to the red sea recommended dkh.

 

[ScottB]

I just realized the way I worded it made it sound like I've already used the RODI system and the Red Sea salt. I haven't used it yet the water I tested was from my local fish store. The RODI + Red Sea is what I'm planning on using and bringing down my current dkh down to the red sea recommended dkh.

OKay yeah I was getting confused there.

You've done 4 tests and they all read crazy. Check.

Salinity was my question. If they mixed your water to 1.040 then sure, I can see getting a crazy dkh. I guess they could spike the water with kalkwasser to jack it up, but not sure why that would be. Or the bucket they used was a previous 2-part alkalinity bucket with a 1/2 of residue on the bottom.

Calibrate your refractometer to confirm SALINITY.

 

[ScottB]

Oh. And return the water and have them test it tomorrow. That is crazy. That water is poison if your numbers are accurate.

I do PT work at my LFS. Yeah, sometimes the DI resin gets depleted (city water is horrible) and a few TDS go out, but always -- every 225G batch == gets reviewed with 2 refractometers before stuff goes out. 1.024 to 1.026

 

[kiran]

I used a refractometer that I calibrated that had a specific ppt of 35 and 2 different hydro meters and the water was testing around 32 ppt. I think the specific gravity was like 1.022 or 1.023.

I'm honestly so confused about all of this. I can't really find anyone else who have had numbers like mine.

 

[TCoach]

As others have said, check your salinity and make sure it is in a normal range. If it is very high, take out ~1% every couple of days and let your RODI water top it back off.

As far as the alkalinity, let it drop naturally if you have any corals. If you want to do a water change, match the alk of your new water with where the tank is at that time. Use baking SODA if you need to raise the alk. Over time, the corals will use up the alk and return it to normal.

Whatever you do, go slow!!!!

This is not an emergency and treating it as such will only make it worse.

 

[mdb_talon]

Salinity was my question. If they mixed your water to 1.040 then sure, I can see getting a crazy dkh. I guess they could spike the water with kalkwasser to jack it up, but not sure why that would be. Or the bucket they used was a previous 2-part alkalinity bucket with a 1/2 of residue on the bottom.

Agree salinity could be an issue. The other factor though is if the LFS is just selling tapwater. Dkh can get sky high pretty quick when using tapwater with a high dkh salt mix.

 

[Aqua Man]

Dkh can get sky high pretty quick when using tapwater with a high dkh salt mix.

I’ve always heard that something (calcium) would precipitate out at extremes. 21DKH seems pretty extreme to me!!

 

[kiran]

I’ve always heard that something (calcium) would precipitate out at extremes. 21DKH seems pretty extreme to me!!

Yeah I've heard of that too. I'm gonna run a few calcium tests today and if I can get away with adding some if its low and get some of that dkh out.