Alkalinity swings

[Spschampion]

Hi, I have a question for those more experienced reefers. I check my alkalinity pretty routinely. I use about 2.5 ml of alkalinity a day and drop approximately .3 of a DKH per day with nothing added. While this seems to remain fairly constant, I occasionally find that there is days where the DKH drop is less. If my dosing remains the same amount I have a slight rise in DKH. It’s not much so I doubt it matters, just wondered if this is a normal thing?

 

[SuncrestReef]

I'm no expert in the subject, but my understanding is that alkalinity consumption will vary based on calcium levels, magnesium levels, lighting, pH, and temperature.  I'll assume your lighting and temperature are consistent day to day, but how often are you testing your calcium, magnesium and pH to see how they compare on days you notice the smaller alk drop?

Also, keep in mind all test kits have a margin of error.

[CrabbyCrabs]

Don't forget to do your tests at the same time each day. I pretty much stopped testing because the test kit colors never match the cards they give you so it's a best guess. That and I'm partially color blind from years of welding. I do like the Hanna alk checker as there's no real guesswork besides eyeballing the vial water level.

[Spschampion]

To be honest, I only test calcium and magnesium once a week. They usually stay within 20 ppm range

[SuncrestReef]

4 minutes ago, Spschampion said:

To be honest, I only test calcium and magnesium once a week. They usually stay within 20 ppm range

What’s your water change schedule, and have you tested a fresh batch of saltwater to know the parameters?

[Spschampion]

15 gallon water change every other week. Fresh batches of water have been tested by me at 

8.5 alk

450 calcium

1350 magnesium

I keep parameters pretty much the same except I run the magnesium up to 1450. 

 

[lewisriverfisherman]

5 hours ago, Spschampion said:

While this seems to remain fairly constant, I occasionally find that there is days where the DKH drop is less. If my dosing remains the same amount I have a slight rise in DKH. "It’s not much" so I doubt it matters, just wondered if this is a normal thing?

What is its not much? Need more info. I think as long as your not swinging more than .5 in a given day you should be good

[Spschampion]

The increase is usually only .3 dkh higher

[The ReefBox]

My personal guess is the test kit you are using (human error) and not checking at the same time each time you test. Are you also adding calcium at equal parts? Usually they are consumed at a 1:1 ratio 

[CrabbyCrabs]

I learned a hard lesson with equal dosing. My tanks don't tolerate it. I have to test and dose each at the required levels but... Now I learned to only dose ALK as trying to bring each into spec cause the others to go way out, at least with reef crystals as mag was always way high. I switched to salinity 6 months ago and have not tested anything but ALK which is low in the 5 range. I do weekly 5-6 gallon water changes. I had the same problem with reef crystals. My tank went way unstable when I switched from dosing alk only to b-ionic. I will never use b-ionic again. That's when all my issues began, except the Cali tort loves everything no matter what.

[Spschampion]

I have been testing weekly. Unless something goes way out of wack. I test each major element independently and dose accordingly. I’ve noticed that my alkalinity drops at a larger rate when calcium is in the 420ppm range. I initially thought that maybe the corals were just absorbing more of each element and this was the “sweet spot”. Now I’m wondering if it is due to an imbalance? Alk ranges 8.3 to 8.7

[CrabbyCrabs]

Randy Holmes Farley has a lot of good info about this on the net. But... I tried the equal dosing he recommends with b-ionic and it cause more issues and the numbers were way out of whack so I just did a bunch of water changes to get it straight again. I think the most important is stability. My alk hovers around 5.5-6 or so on the Hanna checker and look at that Cali tort. My water change water is around 9. I almost don't want to bring it up and steady cause that tort would take over the tank

[Spschampion]

That’s a good problem to have. I’ve been wondering. I have roughly 25 different species of sps and LPS. They’re mostly frags or maybe a little bigger. I don’t use much calcium or other elements on a daily basis. Maybe 2 ml of calcium, alk, and mag. I hear of people with colonies using like 25ml a day calcium. I guess as the colonies get larger I’ll use more? Just surprised my elemental use is so low for how much I have.

[SuncrestReef]

1 hour ago, Spschampion said:

That’s a good problem to have. I’ve been wondering. I have roughly 25 different species of sps and LPS. They’re mostly frags or maybe a little bigger. I don’t use much calcium or other elements on a daily basis. Maybe 2 ml of calcium, alk, and mag. I hear of people with colonies using like 25ml a day calcium. I guess as the colonies get larger I’ll use more? Just surprised my elemental use is so low for how much I have.

I have to dose about 100 ml per day of calcium to maintain 420 ppm in my Reefer XL 425.  I have nearly 100 frags and colonies, ant they're on a growth spurt!

[albertareef]

1 hour ago, SuncrestReef said:

I have to dose about 100 ml per day of calcium to maintain 420 ppm in my Reefer XL 425.  I have nearly 100 frags and colonies, ant they're on a growth spurt!

Ever consider a reactor?  Less programability in some ways (although you can control pH and flow) but often the choice for higher demand systems - I think Brian just switched over recently.  Of course, it wouldn't provide the same type of integration with the Trident 😞

[SuncrestReef]

3 minutes ago, albertareef said:

Ever consider a reactor?  Less programability in some ways (although you can control pH and flow) but often the choice for higher demand systems - I think Brian just switched over recently.  Of course, it wouldn't provide the same type of integration with the Trident 😞

A calcium reactor is in my plans for my next tank, once I build the addition on the house with the dedicated fish room (hopefully next year).  For now, I don't have any space inside my cabinet for a reactor and I don't want external equipment.  My Reefer is like a piece of furniture in a very clean living space, and I promised my wife it wouldn't turn it into a chemistry lab environment.

I'm perfectly fine with 2-part dosing for the foreseeable future, even more now with the Trident.

[Spschampion]

Suncrestreef, 

                        So in your experience do corals go through growing spurts? Is this due to the coral being in more favorable conditions? Just curious, still learning   

[SuncrestReef]

1 minute ago, Spschampion said:

Suncrestreef, 

                        So in your experience do corals go through growing spurts? Is this due to the coral being in more favorable conditions? Just curious, still learning   

I can't say for sure.  My tank is just over 1 year old, and last Oct-Dec my corals were growing quickly.  Then at the end of December things went down hill quickly and I lost a lot of corals to brown jelly syndrome.  I spent Jan-Mar cleaning things up and worked on stabilizing my parameters as much as possible.  I think I'm seeing the results from that effort now because April and May has been a great period of growth and healthy looking corals.  I have been diligently testing parameters daily and carefully adjusting my dosing to keep alk & calcium as stable as possible.  Now I have the Trident testing multiple times per day and micro-adjusting the DOS day and night, so it's even more stable now than when I was doing things manually.

[Spschampion]

Thank you for the advice, it goes a long way!