Low dKH but still precipitating when adding 2 part - need advice please

[jkobel]

Been in the hobby about 10 years but always just flew by the seat of my pants. Never really worried too much about testing or additives and had reasonable success.

Over the summer I had a major crash and things are now back to healthy and I'm really trying dial in my parameters to see how successful I can be.

My dKH is a little low so I've been adding Seachem 2 part regularly. Its not climbing (seems stuck) and now when I add it, it precipitates.

My thought was that precipitation occurs when your dKH levels are saturated but if that's true what is that saturation point based on?

Any help on getting this level up to the 8+ range is appreciated. I'm using the RedSea KH Alkalinity test kit and its vague at best to read.

Thanks!

pH - 8.2
NO3 Nitrate - 0
NO2 Nitrite - 0
NH3/NH4 Ammonia - 0
KH Alkalinity - 7.5 dKH
Salinity - 1.023

 

[nereefpat]

Do you test for Mg or Ca? Could be the Ca precipitating due to low Mg or alk.

Also, if you get that s.g. up to 1.026 instead of 23, your alk will be higher.

 

[cougareyes]

+1 check your mg.

 

[oseymour]

+2 check your mag, if your salt mix is probably low in magnesium and every time you do a water change you would be lowering your mag levels

I prefer to do large 30 to 40% monthly water changes instead of small weekly changes and I have to dose magnesium after every water change because the IO salt is low in mg. Otherwise, I get precipitation.

 

[jkobel]

Interesting. I dont check Ca or Mg, I assumed the precipitation was from low Alk. With regular water changes should Ca and Mg take care of themselves?

 

[jkobel]

Sorry, missed your post oseymour. That does make sense, I also use IO.

is mag is low, what's the best way to raise it?

 

[Jeremiah_Conway]

Interesting. I dont check Ca or Mg, I assumed the precipitation was from low Alk. With regular water changes should Ca and Mg take care of themselves?

That depends on salt mix you use.
Good idea to test new water before adding to tank.

 

[oseymour]

Interesting. I dont check Ca or Mg, I assumed the precipitation was from low Alk. With regular water changes should Ca and Mg take care of themselves?

It depends on your tank so it's hard to give a definitive answer. How old is your tank? And is it high demand?

For some softy and Lps tanks, regular water changes takes can take care of alk and cal needs. I was using regular instant ocean salt for a while and it was low in magnesium so I had to dose that. I started using Reef Crystals recently and its much better.

Also a lot of the 2 part pre-mixed additives combine the magnesium and calcium into one.

Before you do anything else, test your alk, magnesium and calcium and post the results. We'll help you get them up to optimal levels, then test around the same time every day for a couple of days to try and get an idea of how much alk and calcium your tank uses day to day to set up a dosing regimen.

I use the BRS two part system. My tank is 2 months old and has 92 gallons between tank and sump, it is medium stocked with corals, but they are mostly small frags and coralline algae has started to appear and is growing well on the rocks. My tank uses 15ml of alk and calcium per day to keep levels steady at 8.5 Dkh and 420 calcium.

 

[cougareyes]

Depending on your stock and the salt mix you are using, water changes alone will not suffice. Mainly check your ca, alk, and mag and dose accordingly. Maintaining the proper balance between the three is very important. At 7.5 dkh I would say keep your ca around 420-430, and mg is usually around 3x your ca, so at around 1260-1290.

 

[jkobel]

Thanks for the feedback everyone.

Here's a question:

When I test my Alk with this test kit I start with 1 drop of solution and then add one drop at a time. The test kit tells you to count the drops you add and 1 drop = 1 dKH.

I have been assuming that you dont count the first drop that starts the test and you only count all the other drops. Is that correct, or should I be counting the initial drop?

This is the test kit: http://www.bulkreefsupply.com/red-sea-marine-care-test-kit.html

 

[oseymour]

I have a Red Sea alk kit that I use periodically and that's not how it works. I drop until it changes color and then measure how much I've used in the syringe to calculate DKH.

 

[jkobel]

yeah, thats the upgraded test kit. I think I'm going to have to pull the trigger on that to test dKH/Ca/Mg

 

[nereefpat]

Thanks for the feedback everyone.

Here's a question:

When I test my Alk with this test kit I start with 1 drop of solution and then add one drop at a time. The test kit tells you to count the drops you add and 1 drop = 1 dKH.

I have been assuming that you dont count the first drop that starts the test and you only count all the other drops. Is that correct, or should I be counting the initial drop?

This is the test kit: http://www.bulkreefsupply.com/red-sea-marine-care-test-kit.html

With a titration you should count all the volume you add, including the first drop.

 

[jbvdhp]

yeah, thats the upgraded test kit. I think I'm going to have to pull the trigger on that to test dKH/Ca/Mg

go with salifert. It's probably your magnesium.

 

[d2mini]

Thanks for the feedback everyone.

Here's a question:

When I test my Alk with this test kit I start with 1 drop of solution and then add one drop at a time. The test kit tells you to count the drops you add and 1 drop = 1 dKH.

I have been assuming that you dont count the first drop that starts the test and you only count all the other drops. Is that correct, or should I be counting the initial drop?

This is the test kit: http://www.bulkreefsupply.com/red-sea-marine-care-test-kit.html

In the kit's i've use that are similar, you count every drop.
But i'd pick up a salifert or red sea pro kit so you get more accurate readings with decimal points, e.g. 8.5 dkh.

 

[jkobel]

Thx everyone. I just heard back from Red Sea and they say to include the first drop which makes sense but the instructions are vague. That puts my dKH at 8.5 which is better.