Water changes when dosing?

[b4tn]

One thing I have never really figured out is how to do a water change while dosing. I still want to do bi weekly water changes. My train of thought is that even when adding calcium and alkalinity the change will help replenish trace elements as well as help with export even though between filter socks, algae scrubber, and skimmer export is not a huge issue. But if I have a stable 8.3 dkh and 420ppm calcium level how do I keep the levels the same doing a 10% change of 5 gallons if my salt mixes at 13 dkh and 490ppm? Is it best to find a different salt to use? Or is there a trick?

 

[Goneaway562]

In my experience, find a salt that mixes to your tank parameters. Based on those you mentioned, the Red Sea blue bucket would work great!

 

[Rcollick]

I would look to find a salt that's as close to the parameters your trying to keep. It makes things much more simple. Red sea blue bucket mixes pretty close to what your looking for. Dkh is slightly lower. What brand salt are you using now.

 

[b4tn]

The blue bucket salt seems spot on actually. Most of the salts I was looking at mixed much higher. Right now I use reef crystals mainly because its easy to get local.

Blue bucket

• pH: 8.2 - 8.4
• Alkalinity: 7.8 - 8.2 DKH
• Calcium: 420 - 440 mg/l
• Magnesium: 1250 - 1310 mg/l
• Potassium: 380 - 400 mg/l

 

[madweazl]

I use muriatic acid to bring fresh mixed water down to my desired alkalinity of about 7.3 dKh. The rest of the parameters are in a range I shoot for.

 

[b4tn]

I use muriatic acid to bring fresh mixed water down to my desired alkalinity of about 7.3 dKh. The rest of the parameters are in a range I shoot for.

Can you elaborate a little? How does it work?

 

[madweazl]

Can you elaborate a little? How does it work?

Essentially, I add 3ml of muriatic acid to a five gallon bucket to drop Instant Ocean from about 10.7 dKh to my desired level of 7.3. I'm using the low fume version (20% hydrochloric acid) so it take a bit more than the standard (around 30% I believe).

For 30%, I believe it's gallons x desired drop in dKh (e.g. 3.4 dKh in my case) x .123 = ml of muriatic acid to dose
5x3.4x.123=2.1ml

Edit: once complete, the mix needs to aerate for a substantial amount of time to vent excess CO2 so the pH comes back up (I usually mix it over night).