Dosed Coralline algae from ARC and calc/alk uptake through the roof!

[spicymikey]

I am getting confused and concerned by how much calc and alk I am dosing since dumping 4 bottles of Coralline spores from Atlantic Reef Conservatory last month. Looking for some input and thoughts please.

Here's the story. I started a new 400 gal tank on May 7th. Felt it was fairly well cycled by mid June. During that time calc was going nowhere and alk and PH were not difficult to maintain with regular dosing of Sodium Carbonate. Not all my equipment and setup is complete so I've decided to keep livestock out of the tank for now and just keep the cycle going with daily ammonia doses. But I bought and dumped 4 bottles of coralline spores from ARC about 3 weeks ago to get that started. I'm using dry Marco rock. Immediately, the next day, my calc and alk uptake took off. About 30ppm drop per day of calcium, and alk needs proportionately increased.

At first I thought it was great and a good sign that these live spores were growing. But its been about 3 weeks and the calc and alk uptake is increasing to seemingly unbelievable numbers. I am now dosing about a gallon of pre measured bags of BRS Sodium Carbonate and Calcium Chloride pretty much every third day. With that I am still struggling to keep my Alk above 7dKH and my calc above 400ppm. PH is around 8.1. Calcium is precipitating out of the water and settling on things a bit but its not a dust storm. A quick hand swipe across the bottom of the sump shows there is some grit there but nothing significant. I have a crushed coral bed and stirring that up DOES create dust storm. But that is also calcium carbonate and is generally dusty itself.

I am measuring levels with a Neptune Trident, and checking it with a Hanna Colorimeter. I even went and got a Salifert tester to triple check. All are reasonably in line with each other so it seems like the levels are correct. I've had aquariums my whole life and my last one was a 140 reef. But that was 20 years ago. There's been a large gap for me in this hobby and I'm thinking I am ignorant to something important.

Can anyone offer any insight or advice ? BTW, I don't see any signs of Coralline algae yet.

 

[homer1475]

Sounds like it's precipitating out. Thats surely a large amount to be dosing, even for a 400G tank.

Have you checked the impellers on pumps, or heater for white crust forming? Have you checked the entire sandbed to see if any of it is turning hard like rock?

 

[homer1475]

Since there is no livestock in the tank. I would just stop for a week or so, then retest, and see where your at.

 

[spicymikey]

Thanks guys. Yes there is no doubt I have some precipitation. I can easily see it. Just didn't seem that dramatic, and also seems somewhat inevitable with Sodium Carbonate and Calcium Chloride.

I did try stopping calcium dosing and kept going with Sodium Carbonate. Alk level stayed up but calcium kept dropping. When it got down to under 200 I started dosing again fast to get back up. That may be where I started creating more of a problem then I was solving. I'll take the suggestion and stop everything for a week and then start dosing slowly again. There must be more precipitation than I realize

 

[spicymikey]

Just wanted to follow up on this in case someone stumbles across this thread and can benefit from my ignorance and misfortune.

So, it does seem to have been mostly due to precipitation. The bottom wasn't getting hard, and I didn't have a lot of noticeable calcium carbonate crust on things. But when I looked harder in the corners of the sump, and opened the pumps, it became clear what was happening. The other missing tell tale sign of substrate getting clumpy, might be because its course crushed Coral (mostly Calcium Carbonate Aragonite). As I now understand better, Calcium Carbonate can precipitate out more easily when it reaches super saturation (obviously), but also if it bumps into other Calcium Carbonate already encrusted in the tank. So maybe a lot was binding to the crushed coral but not so much "gluing" pieces to each other. Just a thought.

At any rate I solved it by stopping everything, like I said I would, measuring the daily natural uptake, and then resisting dosing anything more than that amount using some reef calculators. I also made the following changes to my dosing practices:

1) Changed Dosing schedule to do Calcium Chloride and Sodium Carb at different hours of the day to avoid any chance of highly concentrated water with Calcium and Carb drips mixing in same area at same time.

2) Moved the Sodium Carb dosing line to right above the overflowing water in the bubble trap to ensure faster dilution and reduce time of high PH in the water around the drops. Its only seconds but I'm learning that can matter. I left all other dosing lines in the same spot.

Been doing this for over a week and the Alk and Calc levels finally (but slowly) rose to acceptable levels. It took patience but I'm now back on track and only dosing about 1/4th what I was when things started going south.