Problems balancing CA,MG, ALK

[mordinad]

Hi All,

I'm having issues raising my calcium.

It is a brand new setup that is about 2 1/2 months old.

75g DT + 20g sump, 60lbs LR and about 10lbs LS
Salt mix is Reefcrystals
Salinity 1.026
Calcium 320, tested with salifert and api test kits
Mg fluctuates between 1100-1200 (I am trying to boost this)
ALK - this has been rising, it is now 14 dKH


In my system I have been dosing Prodibio digest/tim/reef booster. My calcium reactor is a Deltec PF500, which I keep at 6.2ph running 24/7 with a very low effluent (40 drips a minute) with rowalith c+.

I have turned off the calcium reactor to attempt to allow ALK to drop. I have also performed a 25g water change. Calcium levels still 320 after testing the following day. Tank is 2 1/2 months, a couple small fish and several small SPS colonies. Coraline is growing on glass, about 1/4" spots around tank.

Lights are 6x39T5 1 actinic, 2 actinic+, 1 pink, 2 aquablue+, all giesemann. My cerith snails have been very sluggish. Trochus however have been releasing eggs at night.

I am running ATB biopellets for about 2 weeks now. I have a diatom bloom with streaming brown algae. Skimmer is ATB 250 elegance pro, skimming wet with Chaeto in sump on 24/7 daylight bulb. Water movement inside is only 1 vortech mp40. Fish and corals look OK, just snails suffering.

 

[AfricaOffroad]

If you want to up your calcium concentration, you need to run the calcium reactor.
Your alkalinity is very high.
Stop dosing whatever you are using .

 

[mordinad]

The calcium reactor raises the ALK... I was thinking stopping it and adding calcium chloride after my ALK drops to around 10 then restart the calcium reactor to maintain the level.

 

[shifty51008]

I would do what you were thinking. turn off the reactor and dose the tank to get the levels your wanting then you can start the reactor back up to keep the levels where you want them to be

 

[cyphoma]

My 2 cents...

Drop the Alk to 10.
FIRST Raise the Mg to 1400.
Then balance Ca and Alk at 440/9.5-10.

If you get Mg higher, it will help bind up carbonate and leave the calcium higher and available for use in your tank.

Raise the Mg first because it changes the salinity. Keep an eye on that. It's hard to raise all the levels at the same time, especially when they are acting against eachother!

 

[Sk8r]

When balancing, always raise mg first, THEN alk, then cal.

 

[mordinad]

OK, I'll do that. I'll be using Grotech Magnesium Pro instant and Marinium Magnesium Booster. Let me know if anyone has concerns about those two products. I know a store that has the kent but these ones I have on hand in powder form.

I got a feeling this reefcrystal batch has high alk to start. I forgot to test it when I made the 25g water change. Thanks guys.

 

[Sk8r]

Don't know either of those products, but mg is mg, so it should be fine. Once that's up, then your buffer is already high, so the next thing should be your calcium.

I don't know if you're running a reef ---you didn't say what kind: but if you're having cal drop that far out of balance, maybe you are. If you get that water back in balance, just add a teaspoon of Mrs Wages Pickling Lime, or Kalk Powder, to your topoff reservoir, stir once, lid it tightly, and it will hold your water in balance until your mg runs out or your reservoir runs dry. Keep doing the same, and dosing mg before it drops below 1300 and it will hold without ANY other dosing nearly forever... I think it's been 3 months since I had to add mg or alk or cal independent of the kalk drip.

 

[mordinad]

mixed reef, I do have some fairly large SPS colonies in there but nothing that should have dropped the CA so low (if it was ever at 400). I'm pretty positive the high ALK is holding back my CA because there was some precipitation in the water column.

I will raise MG as previously suggested and monitor calcium/ALK every couple days. I want to run at 9-10 dKH. The tank will be SPS dominated with zoas carpeting the bottom.

 

[streak]

Do you have a selinoid that can turn on and off your ca aflunet when your ph is that low.. say then it drops down to 6.4 in afluent.. and come back on at 6.6? 6.2 is pretty low unless you have a pretty good volume to overcome.. and might be part of your stibility problem. You might need a controller for it.. one for the ph probe and one for the seinoide comming off the co2 tank.

 

[mordinad]

Not sure but I read rowalith c+ needs a much lower PH to melt. On the UK forums they say around 6.1 so I've been running 6.2-6.3

My PH is ok in the tank, night time 8.1, daytime 8.3. Just this damn ALK keeps creeping up so fast.

I know CA is used up by animals and so on, is there anything that will push ALK that I should be looking for aside from the CA reactor? I don't add anything to the tank except fresh RO/DI with 0 TDS and prodibio to control my algae. The tank is less than 3 months. LR was from an established tank which I scrubbed a bit and cooked for 2 weeks in a covered heated VAT with fresh saltwater. I already went through a massive green algae bloom the first month. That's gone now. Now it's brown algae (diatoms) that's going down.

I do run D-D carbon and also high quality GFO but weening it off hoping the bio pellets kick in some day.

 

[bertoni]

You need to get some calcium chloride to raise the calcium level. The reactor can't do that without overdosing alkalinity. To raise the calcium level by 100 ppm, the dKH would go up 14 dKH. So I'd dose no more than 100 ppm of calcium per day, and try about 50 ppm for the first dose. This calculator might help:

http://reef.diesyst.com/chemcalc/chemcalc.html

If you want to drop the alkalinity, just turn off the reactor. You can use calcium chloride to keep the calcium level at its current level.

The magnesium level is fine, but I would raise it to 1280 ppm, which is about the canonical ocean average. You can do that at any time.

 

[mordinad]

Hi JOhn, yeah that's exactly my plan. I'm currently dosing MG right now trying to raise 25/day in the morning while I wait for the ALK to drop. I put a little bit of cacl in the evening. I'm monitoring ALK now daily to see the average drop and I'll try to set my CA reactor to match this once I have 8-9 dKH and my calcium is up to 400ish.

I hope it drops quick, I'm leaving for a business trip on friday for 2 weeks. Might just leave the reactor off and put lights on for only 6hrs and skim dry.

 

[GT_Jacket]

Check your salt mix also. Some can be way out of balance.