Alk consumption gone wild!!

[eskymick]

For the past several months, I've been needing to continually increase my alk and calc dose to maintain proper reef levels.

Using Randy's two-part, I am now up to a dose of 1200 ml per day of both alk and calc. I find that to be WAY out of the ordinary. With that dose, I am struggling to maintain alk at 8 dKH. I also find that my calcium level slowly increases beyond acceptable levels (so I remove the calcium dosing tube one day out of the week).

I've read on here that most reef tanks consume 2 to 3 dKH units per day. In my volume of water (175 gallons), my dosing regimen would indicate that my reef is consuming approximately 10 dKh units per day.

I only have a few coral colonies in my reef .. none of which are growing at any unusual rate. In fact, I hardly see any growth.

I've been making it a point to keep my mag level up. I dose Randy's mag solution to keep the level at 1400.

Has anyone else experienced this? What can I do to bring alk consumption back in line?

 

[ChuckG]

Are the current levels in balanace?

Coraline algea can be a big consumer of alk and calc and could be a suspect if you have dense populations.

 

[eskymick]

Are the current levels in balanace?

Coraline algea can be a big consumer of alk and calc and could be a suspect if you have dense populations.

Yes, the levels are in relative balance. At this dosing level, the calcium level does creep up slowly, however.

I have absolutely no coraline algae growth. And, now that you mention it, that adds an extra bit of strangeness to this problem, too.

 

[chuckreef]

Please describe exactly how (and when) you are adding the two parts?
What if you try just maintianing alkalinity with baking soda (dissolved in a little RO) for a few days, then tell us the quantity per day required?

 

[eskymick]

I'm dosing with an Innovative Aquatics dosing pump. I measured the output at the current setting and it's dripping at the rate of 50ml per hour. The pump is operated 24/7.

 

[ChuckG]

No precipitate build up anywhere.. on the heater or pumps?

How about your test kits.. have you tried a second one, or used a known reference to make sure your readings are valid?

 

[eskymick]

No precipitate build up anywhere.. on the heater or pumps?

How about your test kits.. have you tried a second one, or used a known reference to make sure your readings are valid?

Until I kept a better eye on the mag levels, I would get precipitate on the pumps and heater. But now that the mag has been maintained at a level over 1350, that is no longer a problem.

I use LaMotte alk test kits. I have two of them .. one is nearly finished up and one I purchased a couple weeks ago. They both give me the same alk readings.

 

[ChuckG]

In my volume of water (175 gallons), my dosing regimen would indicate that my reef is consuming approximately 10 dKh units per day.

If you stopped dosing altogether for a couple hours would you see the levels drop the same amount that you are actually dosing? At 10dkh per day this should be just under 1dkh every two hours?

Seems odd that so much needs to be added when there is not much there to actually deplete alk and calc. What about bio load.. could there be a large population of nitrifying bactera involved with some of the consumption?

 

[eskymick]

If you stopped dosing altogether for a couple hours would you see the levels drop the same amount that you are actually dosing? At 10dkh per day this should be just under 1dkh every two hours?

Seems odd that so much needs to be added when there is not much there to actually deplete alk and calc. What about bio load.. could there be a large population of nitrifying bacteria involved with some of the consumption?

Yes, my alk falls very fast if not dosed. I fear that if my dosing pump would fail the alk would fall so fast that I'd have a system crash.

For livestock, I have a light to moderate load. The largest fish in my reef is a 3" copperband butterfly. Everything else is rather small ... pair of clowns, neon dottyback, pygmy angel, bi-color blenny, 2" fox face, and a 2" Tomini Tang.

 

[chuckreef]

I'm dosing with an Innovative Aquatics dosing pump. I measured the output at the current setting and it's dripping at the rate of 50ml per hour. The pump is operated 24/7.

 

[chuckreef]

I'm dosing with an Innovative Aquatics dosing pump. I measured the output at the current setting and it's dripping at the rate of 50ml per hour. The pump is operated 24/7.

But how, where and when? (e.g., presumably you meant with two dosing pumps (not one), but is one routed to the tank & one to the sump, and are they on at different times - or are they right next to each other in a low flow area of the sump & running simultaneously (just for example) ---> the details might reveal the problem (presuming there is a problem).

 

[eskymick]

But how, where and when? (e.g., presumably you meant with two dosing pumps (not one), but is one routed to the tank & one to the sump, and are they on at different times - or are they right next to each other in a low flow area of the sump & running simultaneously (just for example) ---> the details might reveal the problem (presuming there is a problem).

It's your typical two-channel dosing pump. I dose into the sump. I'm careful not to let them dose together. I also have a Koralia 4 powerhead in the sump to get everything well mixed.

 

[crewchef]

Florida rock? Do you have any (a lot of) bi-valves on your rock? Took me a while to figure out that was what was driving up my dosing requirements. Mine is a nano so much smaller but cut my dosing in half after removing all but one bi-valve off my rocks.

 

[chuckreef]

It's your typical two-channel dosing pump. I dose into the sump. I'm careful not to let them dose together. I also have a Koralia 4 powerhead in the sump to get everything well mixed.

I would try miantinaing alk with just plain baking soda for a few days. At least this will, let you know if the high alk demand is real, or if its an artifact resulting from something going wrong with preparing/ dosing solutions. Although it appears your on top of everything that could go wrong, I still find it difficult to believe the alk demand can be that high.

 

[pfy333]

Not a expert by far, but throwing this out there. Maybe your solution isn't as concentrated as you think it is.

 

[eskymick]

Thank you to all for the input. For now, I've decided to let only the alk drip into the sump via the dosing pump. I removed the calc from the sump and I will dose it manually into the display reef. I'll test twice daily.

 

[eskymick]

Florida rock? Do you have any (a lot of) bi-valves on your rock? Took me a while to figure out that was what was driving up my dosing requirements. Mine is a nano so much smaller but cut my dosing in half after removing all but one bi-valve off my rocks.

I have no bi-valves at all.

 

[lex211]

What are bi-valves ?

 

[eskymick]

What are bi-valves ?

Clams, scallops, oysters.

 

[eskymick]

Last evening, I removed the calcium dosing tube from the sump and reduced the alk dose rate from 50 ml per hour to 40 ml per hour. The alk reading at this time was 8.7 dKH.

Twelve hours later, I took another alk test. This time it read 7.6 dKH.

Not so good, eh.