Alk creeping with auto water changes

[conlan75]

alright - I'm stumped on this. Tank is 3 months old, PH is between 8.1-8.2, Salt is at 33, MG is 1240, Calcium is 480 and Alk keeps creeping from 11 into the 12's. It got as high as 14, with Ca and Mg relatively the same. If I do a 30% water change, Alk drops some, I was able to drop it from the 14 to 11 by doing day after day changes. I put in a DOS and setup auto water changes, started at 5gal a day, then with Alk creeping up, I bumped it to 20, still no slowing the alk creep. I switched from IO to Red Sea their blue bucket so alk tests at 8 in a fresh batch. Where as the IO was testing at 11dkh.

the only dosing I'm doing is for NO3O4-X.
It is a mixed tank - however everything is fairly new, I haven't lost anything yet, but really don't want to either.

Any thoughts or expert advice? My local store is stumped and I'd like to be able to take a work trip or two and not be thinking about water chemistry when I should be focused on customers tech.

 

[Randy Holmes-Farley]

What exactly does this mean?

"the only dosing I'm doing is for NO3 pO4-X."

 

[conlan75]

nutrient control for algae. I haven't had to dose for Alk, Ca or Mg. Except from what I'm being told I should bump my Mg level up a little. But that doesn't impact the Alk from what I've read.

 

[Randy Holmes-Farley]

nutrient control for algae. I haven't had to dose for Alk, Ca or Mg. Except from what I'm being told I should bump my Mg level up a little. But that doesn't impact the Alk from what I've read.

Still, what exactly does it mean?

You are using a product NO3PO4X, or are you dosing nitrate and phosphate?

Both nitrate dosing and declining nitrate add alkalinity. That is why I'm obsessing on this.

 

[Miami Reef]

You are using a product NO3PO4X, or are you dosing nitrate and phosphate?

Both nitrate dosing and declining nitrate add alkalinity. That is why I'm obsessing on this.

I think OP is using Red Sea NOPOX which is vinegar and vodka.

 

[Randy Holmes-Farley]

If you are using NOPOX, then the question is what is happening to nitrate. if it is declining then that may explain the alk rise.

A drop of 50 ppm nitrate adds 2.3 dKH.

 

[Miami Reef]

If you are using NOPOX, then the question is what is happening to nitrate. if it is declining then that may explain the alk rise.

A drop of 50 ppm nitrate adds 2.3 dKH.

Can NOPOX lower nitrates that fast? I don’t even think his tank has the amount of denitrifying bacteria that can accomplish such a rapid nitrate removal. I don’t even think a 3 month old tank can achieve >50ppm unless grossly overfeeding. Especially since this user is doing so many water changes.

@conlan75 What test kit are you using? API?

 

[Miami Reef]

I’m thinking that you aren’t giving your alk enough time to get lower. Seems like you Reef Crystals was shooting your alk.

I’d say give it a few weeks of your water change schedule and it should balance to 8dkh.

Also, I’m assuming you aren’t dosing any PH buffers, right? And obviously no alk additives?

 

[Miami Reef]

Also, do you use tap water for top offs/water changes?

Answering these questions will be very useful to us.

 

[Randy Holmes-Farley]

I do not know how fast he said it happens over. He said creeping from 11 to 12, sometimes 14. That need not be fast.

It need not be denitrifying bacteria. Typical aerobic bacteria can also consume nitrate and make their tissues from it.

But there certainly are other reasons for alk to rise.

 

[conlan75]

Can NOPOX lower nitrates that fast? I don’t even think his tank has the amount of denitrifying bacteria that can accomplish such a rapid nitrate removal. I don’t even think a 3 month old tank can achieve >50ppm unless grossly overfeeding. Especially since this user is doing so many water changes.

@conlan75 What test kit are you using? API?

Trident and backed it up with Red Sea's Alk test. I also just recalibrated the Trident to be safe. Nitrite and Nitrate test's show 0ppm. just trying to cut back on the algae that's growing in the tank.

 

[Miami Reef]

Trident and backed it up with Red Sea's Alk test. I also just recalibrated the Trident to be safe. Nitrite and Nitrate test's show 0ppm. just trying to cut back on the algae that's growing in the tank.

What’s your phosphates level? Post a picture of your algae. You mentioned about this algae for a while already. At 0 nitrates, I would expect that your algae would be on the lower end.

FYI: Red Sea NOPOX removes nitrates better than phosphates. It can even cause the nitrates to hit 0 while phosphates are still very high.

The problem is that your phosphates cannot be lowered with NOPOX when you have 0 nitrates. The bacteria uses the nitrates to lower the phosphates.

As I mentioned above: I need a phosphate testing. If it’s elevated, I’d ask you to run GFO.

 

[Miami Reef]

But in either case, I think I’d stop the NOPOX dosing. It isn’t helping your algae problem and only making it harder for yourself to stabilize the tank.

 

[conlan75]

I do not know how fast he said it happens over. He said creeping from 11 to 12, sometimes 14. That need not be fast.

It need not be denitrifying bacteria. Typical aerobic bacteria can also consume nitrate and make their tissues from it.

But there certainly are other reasons for alk to rise.

ok - I didn't know that - the shop that comes out every two weeks always says that the nitrite and Nitrate is always low and acceptable. I've recently started testing it. Here's a time frame - Wednesday last week I had it at 11.3dkh, today at noon it tested at 12.3dkh. I've turned off the dose of the algae control and will do another water change and then monitor.

 

[conlan75]

What’s your phosphates level? Post a picture of your algae. You mentioned about this algae for a while already. At 0 nitrates, I would expect that your algae would be on the lower end.

FYI: Red Sea NOPOX removes nitrates better than phosphates. It can even cause the nitrates to hit 0 while phosphates are still very high.

The problem is that your phosphates cannot be lowered with NOPOX when you have 0 nitrates. The bacteria uses the nitrates to lower the phosphates.

As I mentioned above: I need a phosphate testing. If it’s elevated, I’d ask you to run GFO.

Phosphate tester is the one test I don't have - just ordered it. I'll take a picture here shortly and post.

 

[conlan75]

Phosphate tester is the one test I don't have - just ordered it. I'll take a picture here shortly and post.

Phosphate tester is the one test I don't have - just ordered it. I'll take a picture here shortly and post.

Ok, so I turned off the doser. Ran 10 gallon water change last night and Alk dropped to 11.5. In the morning the glass is usually covered in brown algae. This am, not so bad. I’ve attached some pics.

 

[Miami Reef]

Ok, so I turned off the doser. Ran 10 gallon water change last night and Alk dropped to 11.5. In the morning the glass is usually covered in brown algae. This am, not so bad. I’ve attached some pics.

That looks like diatoms. Completely normal for a new tank and they go away on their own with time.

 

[Miami Reef]

@conlan75 How many gallons is your tank?

 

[Randy Holmes-Farley]

ok - I didn't know that - the shop that comes out every two weeks always says that the nitrite and Nitrate is always low and acceptable. I've recently started testing it. Here's a time frame - Wednesday last week I had it at 11.3dkh, today at noon it tested at 12.3dkh. I've turned off the dose of the algae control and will do another water change and then monitor.

If they are correct, then nitrate decline is not the issue.

Top off water is what?

 

[conlan75]

@conlan75 How many gallons is your tank?

The tank is 150 gal (Red Sea Max S 650)