h2so4hurts
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API KH for 5ml is 1 dKH per drop. You can make it slightly more accurate by testing 10ml in a bigger vessel
Normal pH + high dK
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ShrimpBandit
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Just tested the source water and here's what I have:
Salinity: 1
pH: 7.8
dKH: 6
Re-tested tank water about 48 hours after weekly 10% water change:
Salinity: 1.027
pH: 8.2
dKH: 22 (tested twice)
I even changed the cup and pipettes I used to sample from the tank, just to be sure it wasn't a cross-contamination issue.
Does this help? Any ideas?
Randy Holmes-Farley
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That explains the high alkalinity. It isn't suitable for top off or making new salt water. The alkalinity is much too high.
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ShrimpBandit
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But how does it go from 6 dKH to 22 dKH with just the addition of salt mix? How high is too high for source water?
Randy Holmes-Farley
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Salt mix 13 dKH, water at 6 dKH gets to 19 dKH before hitting the aquarium..
Top off a few times with that tap water and alk will just keep going higher unless you have more demand for alk than the tap water is adding.
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ShrimpBandit
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My noob is showing, but if ideal dKH is closer to 10, then why the heck would salt mix even start that high?
And those numbers are for natural spring water. Guess I ought to check the levels from my tap and see if they're any better? Maybe take a look at the RODI options? Or should I just plan to treat my source water to bring dKH down before I even mix in the salt?
h2so4hurts
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Ideal is 8-9 for an ULNS, if you bump up nutrients you can go higher. Lots of us cut the alkalinity of salt mixes with HCl to match our desired Alkalinity.
Randy Holmes-Farley
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I recommend 7-11 dKH for a normal reef tank. some salts are higher either because those companies think higher is good ((Red Sea coral pro) or so that normal water changes may keep alk from getting too low is low alk demand tanks.
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ShrimpBandit
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I'm using the same source water and salt mix as the original owners of the tank, so it's presumably always been that way. I just wasn't testing for it until now.
Could I just do water changes with the HCl and use distilled water until I can get that level down?
Randy Holmes-Farley
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ro/di is strongly preferred since the alk may not be the only issue with it.
h2so4hurts
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Have you tested your source water? Why aren't you using RODI? That's the best way to know you're not adding any excess Alk calcium or anything else
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ShrimpBandit
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Yeah, test results from source water earlier in the thread - it starts at 6 dKH, which I just learned is problematic.
I'm not using a RODI (yet) because I'm a noob and didn't know I needed one until recently.
My current tank is an inherited fish/crab/shrimp 40g salty that rekindled my interest in the hobby - I'm now curing the rock for a 75g reef setup (the 40g will become my sump) and I plan to get a RODI unit for that build. Part of the reason I even started testing for dKH is to make sure I have a handle on the chemistry before it's go time on the new tank and I introduce new inverts.
dbowman5
Valuable Member
your brain is working, you are coming up to speed with your understanding prior to your upgrade which is the proper order. you are going to be ahead of the curve. keep up the learning!
It is a steep learning curve in the beginning for sure. RO/DI is a default must to stay in the hobby over time, but you have the thinking to get there until then.
With a new or rebooted system shoot for:
Salinity: 35 or 1.024- 1.026
dkh: 7 to 9
Temp 78F
Seek out a salt mix that is lower in dkh. RS Blue is a good one. Later you can go to RS Pro or Instant Ocean RC once you have alkalinity consumers demanding it.
With a new or rebooted system shoot for:
Salinity: 35 or 1.024- 1.026
dkh: 7 to 9
Temp 78F
Seek out a salt mix that is lower in dkh. RS Blue is a good one. Later you can go to RS Pro or Instant Ocean RC once you have alkalinity consumers demanding it.
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ShrimpBandit
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ShrimpBandit
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FWIW, I decided to test my city tap water (as compared to the artesian well water I have been using as source). Here's what I got:
pH: 7.4
Salinity: 1
dKH: 4
Not all that much better, but I'm feeling a little silly for hauling buckets to and from the well every week for the last few months.
Welp, off to research RODI options sooner than I expected..
pH: 7.4
Salinity: 1
dKH: 4
Not all that much better, but I'm feeling a little silly for hauling buckets to and from the well every week for the last few months.
Welp, off to research RODI options sooner than I expected..
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ShrimpBandit
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Just to circle back on this - I bought the RODI system, got everything up and running and did a 25% water change. Waited 24 hours and ran all my tests and here's where I am now:
Salinity: 1.026
pH: 8.2
dKH: 17
Still not ideal, but it's definitely helping since I was sitting at a dKH of 22.
I'll keep up on the weekly water changes and look for a salt mix that might work better for this FO tank. Thanks again for the help!
Salinity: 1.026
pH: 8.2
dKH: 17
Still not ideal, but it's definitely helping since I was sitting at a dKH of 22.
I'll keep up on the weekly water changes and look for a salt mix that might work better for this FO tank. Thanks again for the help!
Krixic
A Tad Obsessed
Not sure if someone already explained this but RO/DI strips water to its purest form. So Alk, Cal, Mag, ect are all 0. When you use your salt mix, it already has the additives that your Saltwater tank will need without you having to dose right away. Threrefore, if your salt mix mixes to 8dKH at 35ppt, then thats what you will get when you mix your salt to that specific salinity.
With RO/DI filters there are plenty to choose from just make sure you get one with a DI resin! Read this R2R article...it explains everything more in depth https://www.reef2reef.com/ams/the-basics-of-an-rodi-filter.754/
I got a 4 stage RO buddy for 70 bucks and it works but you get 1 part of good water to 4 parts waste water so it was not super effective in my opinion. Although if this is for a smaller tank then go for it! Does the job at a affordable price. Otherwise look into BRS systems! I got the Water saver 4 stage and that thing is awesome! It produces at about a 1:1 ratio of waste and good water and is much more efficient. Just be ready to drop closer to 200 but keep in mind these systems are meant to last!
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ShrimpBandit
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Thanks - I bought the BRS 6 stage RODI, and though I haven't tested the water coming out, I trust that it's pure. It's just that my tank still had 75% that was water from before the RODI (I did a 25% change with the new stuff, rather than changing all of the water at once). I think I'm finally headed in the right direction!
Krixic
A Tad Obsessed
Indeed you are! Over time as you do continuous water changes you will dilute the water more and more making any contaminants less dangerous over time. I would get a dual line TDS meter, they are 20 bucks on amazon and are important so you know when your filters need to be changed (namely the DI resin). A lot of people use this one https://tinyurl.com/y2kjnx5b (Just be sure to read the instructions to get accurate readings)
Once your TDS reaches 2 or more, means your DI resin likely needs to be changed. Could also be the membrane or carbon/sediment filter but those last abit longer than DI. You can also get a pressure gauge but thats not super important if you are happy with your current water output. Its mostly to make sure your filter is running at max efficiency and I also think It may be able to tell you when you need to change your membranes (my logic is that if PSI goes higher than normal, then the membranes are maxed out).
