Unstable Paramaters

[Mortaliton]

Good Afternoon

I have been running a Saltwater aquarium now for about 2 years. 125 gallon tank. All equipment besides gyro is running in the sump. I would consider it heavily stocked.

I have a K1-200 protein skimmer

2 media reactors, one is running GFO-HC. Currently phosphates are .1 . I just replaced GFO so it is more elevated than normal but I don’t have an issue with phosphates.

The second media reactor is running TL-Reefs premium bio pellets. It has been 3 months and the pellets are not slimy. I have seeded than dosed with microbacter 7 for 2 weeks following on 2 separate occasions. I will attach a video here, my big question is if I have enough flow going through the pellets. I did have an incident with power and it flickered a dozen times causing some GFO to backflow into pellets. That’s the small particles there. Got most out. Nitrates is about 20 ppm right now. Mixing RODI water now for water change. I make my own and pre mix in a 75 gallon aquarium.

The second question is about my alkalinity. For the life of me I cannot get my kalkwasser reactor to maintain. I am running a Reef Octopus KS-100 kalkwasser reactor. I was running it for 5 minutes every 2 hours. But my kalkwasser seems to deplete in 3-4 days and alkalinity drops to base of about 7.2

I just reduced the frequency to 15 minutes every 6 hours. Maybe I am disturbing it a little too much.

Any info or advice would be very appreciated.

Thank You!

 

[Uncle99]

I would think if you can maintain 20ppm nitrate and .1ppm phosphate in a heavily stocked tank, 2 year mature system, everything is working correctly.

As for the Alk, if it’s consistently low, dose it up along with CA, but ensure MG is in the 1350ppm range and salinity 1.026 and retest before bumping it. That’s to ensure we don’t get inaccurate readings.

The should not flux more than .5dkh at anytime, and should run in the 9ish Dkh range so there’s room on both sides, without falling into danger zone.

 

[Privateye]

You can do a nitrate test on the water exiting the denitrification reactor to see if it's lower than the incoming water. That may be a better way to check than how slimy it is. If there is no difference then I would look into the flow rate.

I'm more of a 2-part doser. I don't deal with Kalk much anymore. I generally use soda ash for alkalinity, but sometimes I use baking soda.

 

[Mortaliton]

Current my magnesium is 1420.

My target alkalinity is 9 but with the mixer losing potency it drops like a rock. It can go from 9 to about 7.4 in about a week. I was dosing about 5 liters a day to maintain. I have a 20 gallon res with RODI water that feeds it.

My target salinity 1.026 but I’m sitting at 1.024 right now. I think the skimmer slowly eats it but I too salt off every few weeks back to baseline.

Calcium is 600+ without corals eating it at the moment dosing Kalk. I have never had an issue with it precipitating out.

 

[Privateye]

That drop isn't too wild. My alkalinity demand has varied over the years, but typically it drops by about 1 dKH per day.

5L is a lot of water to be adding daily though! I buy soda ash (Arm & Hammer) from Walmart and add about 0.75 cups to 1L of water. I mix it with a magnetic stirrer (about $30 on Amazon) and my dosing pump does the rest. It typically doses about 80-100 ml total per day across 4 doses. I need to calibrate the pump though, so it's currently offline.

 

[Randy Holmes-Farley Verified Community Expert]

Can you post a picture of the tank to gauge alk demand?

 

[Mortaliton]

Is soda ash something I can put in my Kalk mixer or is the equipment incomparable?

I have read up on soda ash, baking soda, vodka in reef use but have not researched to much of the dosing yet

 

[Randy Holmes-Farley Verified Community Expert]

Is soda ash something I can put in my Kalk mixer or is the equipment incomparable?

I have read up on soda ash, baking soda, vodka in reef use but have not researched to much of the dosing yet

No. There’s nothing else that one would put in a kalk reactor.

 

[Mortaliton]

 

[Randy Holmes-Farley Verified Community Expert]

so your alk demand is coming from the coralline and possibly accumulating nitrate. Kalk should be able to keep up if evaporation is not too low.

 

[Mortaliton]

I don’t think my ato kicks on to much these days since I am up to 5 liter a day Kalk dosing. However because it exhaust so quick I’m sure it will decrease dosing if I can ever get it under control. I have to test daily going forward but I feel like the kalkwasser loses all potency after 2 days or so. That’s why I am thinking storing every 2 hours is to much.

I just cleaned out the reactor today and refreshed everything. I changed it from 5 minutes every 2 hours to 15 minutes every 6 hours to stir.

Maybe I’m incorrect but I understand it forms a layer after storing which helps prevent exhaustion from CO2. Maybe I’m disturbing it too much. Maybe 15 min every 6 hours is too much still?

I do add Kalk every 7 days to the reactor. I am aware it will lose potency over time but the short span I’m dealing with seems off.

I made my own mesh tops to encourage evaporation as well since my glass lids held in to much as my dose rate and my water was rising. It is stable now.

I was unaware nitrates use alkalinity. Good to know.

 

[Randy Holmes-Farley Verified Community Expert]

I was unaware nitrates use alkalinity. Good to know.

Accumulating/rising nitrate depletes alk, and falling nitrate adds it back. Steady nitrate at any level has no alk effect. :)