Ca, Alk, Mg Dosing and white film buildup on glass

[Oceanus]

Hey NR-

I set up a Nuvo 16 SPS tank back in April and up until this past week or so everything has been trucking along fine. I have seen good growth/PE/coloration and no losses aside from a seemingly random STN on a smoothskinned acro that was about a month and a half old. I have been dosing Seachem's Reef Fusion 2 Part system since I started the tank. This past week I have been getting very significant buildups of a difficult to scrape white, milky substance that I never encountered before. Although the roughly 20 SPS frags/mini colonies and 10 or so LPS are still doing fine, a few have become ticked off in the past few days, with less PE. Additionally, I have been having a really tough time keeping Ca and Alk in range. These are today's readings, from Salifert kits with 2018 expiration dates:
Ca: 310ppm

Alk: 7.1 dKH

Mg: 1455ppm

PO4: Undetectable

NO3: Undetectable

78.5*F

SG: 35ppt

About 5 days ago, my readings were as follows:

Ca: 420ppm

Alk: 7.7dKH

Mg: ~1500ppm

So, my Ca and Alk have fallen rather drastically, more so than they have in one week historical gaps. What really bugs me about this is that I have been dosing 20mL of Ca and 40mL of Alk daily, 10 minutes apart, into the rear chambers (not all at once!). This feels like A LOT for a 16 gallon with maybe 12 gallons of actual volume.

Equipment notes:

AI Nano @ 100% blue, 75% white about 6 inches from water surface

MP10 at 100% flow

2x Hydor Pico 1200 pumps, 300gph each

Stevie T Underwater 10w light with a clump of chaeto that runs on during daytime

Purigen, Chemipure elite, GFO, and filter floss in the filter baskets

12 lbs of LR

20 lbs of LS

Tunze Nano ATO with about .75 gallons a day of evaporation

2x 4 inch cooling fans above the rear chambers, the tank overheats to about 85*F without these

I leave my window cracked open a small amount with the ceiling fan on and have a ton of plants in my room, so there is not much CO2 in the air, probably forcing a higher pH (I don't currently have an accurate kit, will try to get a Salifert tomorrow).

 

The film that builds up on the front and side panels generally manifests every day, and if I don't scrape it daily it becomes extremely thick. I feel like I am over dosing, but my levels are quite low. This buildup does not appear on the rocks, and my sand is not clumping.

 

I also had 2 mysterious invert deaths this past week, my cleaner shrimp turned hazy and passed away and I found my emerald crab dead, black on his back. My yellow coris wrasse and hermits are doing fine.

 

I just received my BRS 2 part dosing kit and will be setting it up over the weekend.

 

So far my best guesses are faulty test kits (sort of unlikely, they expire in 4 years, although against the check solution my Alk kit is reading about .3dKH high). If anyone has an idea to stop this buildup and restore my Ca and Alk levels, I would greatly appreciate your advice. I have attached my Excel reef logbook to the post, this goes back to April and the start up of the tank. Thank you for your time.

 

EDIT:

I forgot my WC schedule. I have been doing 2g water changes weekly with Reef Crystals. I haven't had any problems with this in the past. I use DI water from the local supermarket that tests in at 0-1 TDS. I also use this water in my top off.

[Oceanus]

Did a 2 gallon water change today with Reef Crystals, and my Alk is back at 8dKH, but Ca is down to 275ppm! I am going to the LFS tomorrow for a test kit cross check. This is just too weird now.

[Oceanus]

I think I may have found my problem, after consulting both of the local LFS. LFS 1 said to vacuum the sand and dose less, and LFS 2 said to dose Ca in the morning and Alk at night, so that there is a substantial number of hours in between Ca and Alk doses. Previously I had been dosing them 10 minutes apart and got Alk snowflaking. Yesterday I tried this strategy and got no snowflaking!

Also installing my BRS system tomorrow, so some higher quality additives may make a difference too.

[Oceanus]

While I seemed to be on my way out of the woods yesterday, I had 2 very unpleasant surprises this morning. First, my favorite acro got a few small patches (each one corallite in size) of STN. The reason: apparently my alk went from being 7.3dKH yesterday to 8.6dKH this morning. Weird thing is, I didn't dose more than 20ml of alk yesterday. None of my other acros seem to show any signs of necrosis. The other disturbing thing I found is my Calcium has sunk even lower to 220ppm. It still is precipitating on the glass. I set my BRS Calcium doser on this morning to try and boost Ca up towards 300. Fingers crossed, but I have to go on a 3 day trip starting tomorrow and hopefully nothing else STNs and my favorite acro stops.

[Tamberav]

Seems like a lot of alk to me. I dose 20 ml in my 1 gallon ATO and I have a 45g with a 29g sump. I estimate there is 50 gallons and use BRS calc and about 75% of of the gallon gets used a day. BRS calc for 50 gallons from 7.7 to 8 alk is only 10.7 ml. Perhaps your additive is different but it seems like a ton to dose to a nuvo 16 at one time.

 

If they are sucking down a lot of alk, I would think a doser adding it slowly through the night (or perhaps Kalk in the ATO) would be better than dumping it in all at once in such a small volume.

[Oceanus]

Yes, it seems like a ton. That said, the tank is pretty packed full of SPS. Thankfully I switch over to my BRS 2 part dosers today and am stopping the manual addition of 2 part (Seachem). Thanks for your advice!

On the bright side, my favorite acro is displaying greater poly extension since I upped my calcium back to just under 300. It was totally closed before. No further signs of RTN in the last 3 hours, which is also good.

Precipitation onto the glass will hopefully stop now that I have gotten onto the dosers.

[Oceanus]

So I was out of town until a few hours ago...

I have some rather good news! All of the RTN/STN has stopped and there has been no progression since before I left. Polyps are extended and the rest of the acros/SPS look fine (knock on wood). This is the second time I have ever saved an acro from what seemed like imminent death.

Another piece of good new is with the BRS dosing system, I have gotten no precipitation on the glass!

[Oceanus]

I need to turn up my dosers. It looks like levels fell over the past 3 days to Ca 270ppm, Alk 6.1dKH, and Mg 1335ppm. Surprisingly nothing is looking bad.

[Oceanus]

Bad news...precipitation is back! It is a lot less than would occur in one day before, but is still really annoying. My magnesium was 1335ppm yesterday so I don't know why I can't stop this stupid precipitation.

I currently am using the BRS dosers to dose Ca at 7 a.m. and Alk at 9 p.m.

Thoughts?

[Tamberav]

Spread the dosing out over several + hours in small increments might help. So if you would do 20 ml, dose 3.3 ml once every hour for 6 hours.

 

It is being dosed in a high flow area, correct?

 

No expert, but that is what I would try. Plus it should give a little more stability.

[Amphiprion1]

Have you had your test results verified by another source to be safe?

 

If the above conditions tamberav mentioned are verified, it sounds to me like potential overdosing. The confounding thing about overdosing is that it can make it seem like usage is substantially higher than it actually is. It is also much easier to do that one might think. If pacing doses does not help, I recommend a water change and subsequent observation. Give the tank a day or so after the change to stabilize and then begin testing and observe how much is actually being used. Use a calculator to find a rough estimate of how much supplement you might need and start dosing at 50% or so of what is recommended and dose slowly in intervals. This is important, since it is an estimate at best and there can be quite a bit of error involved when accounting for test kits, measurement, etc.

 

FWIW, in my 40g tank/50g system (granted usage is pretty low to begin with, but I do have fast growing corals), I am using right around 25 mL daily of a homemade bicarbonate 2 part additive. It is roughly 1/2 the concentration of homemade carbonate-based supplements and roughly 1/3 the concentration of commercial supplements.

[Oceanus]

Thanks guys. I just realized I made a pretty dumb mistake with dosing. I was dosing Alk in the evening and Ca in the morning, but pH is highest around lights out time and this probably lead to higher precipitation.

I am dosing into a very high flow area. Should probably get my tests verified.

I just did my last RC water change and found the levels to be low, 6.1dKH and 380ppm Ca. I bought some H2Ocean and am mixing up a 4 gallon batch to change out tomorrow.

I am changing my dosing to 26mL of Alk per day and 24mL of Ca per day. Overdosing seems like a culprit upon reading this article: http://reefkeeping.com/issues/2005-07/rhf/index.php

The problem currently is I feel my levels are unsafe. This afternoon I measured 275ppm Ca and 6.4dKH Alk.

 

Unfortunately I can't split the doses out over multiple times per day. My timers only work for 1 period of on per day.

Fingers crossed that the salt change and dosing change work!

[Tamberav]

I would probably just invest in a used RKL assuming it can control dosers out of the box.

[Oceanus]

I do have an RKL on my 125 and it's been pretty good. I should look into one for this tank.

[Oceanus]

It's been a while...and there's some good news, and some bad news. The good news is that all of my SPS have been doing fine, and Alk is pretty stable around 7dKH. Most of the precipitation has stopped.

The bad news...Calcium is still really low for some reason (250ppm) and I can't seem to get it to rise unless I do a WC with my new salt. There is some precipitation on the glass still, but rather than a light covering that fogs the whole glass it appears in patches. Any thoughts?

I am uploading some pictures of it to post later today...

[Oceanus]

http://s93.photobucket.com/user/oceantanks/media/170_zps0af9f9c0.jpg.html'>

[NaturalViolence]

That's CaCO3 precipitate. I got the same thing back when I was using sodium carbonate and calcium hydroxide for dosing. Try switching to sodium bicarbonate for the alk portion of your dosing. And use a razor blade to scrape off the existing precipitate.

[Oceanus]

Hmm that's interesting. I will try and switch to bicarbonate. I am not using Calcium hydroxide though, using Calcium chloride.

 

I really need to go get a pH test kit.

[Oceanus]

Buying a pH kit today and probably ordering BRS bulk Sodium Bicarbonate... what's really strange about the recent precipitation is that when I remove it it appears in exactly the same spot the next day. It doesn't occur on ~70% of the glass, and it always occurs on the other 30% in the exact same formation.

Anyone got an idea about my nasty low calcium levels? I am getting pretty frustrated and have been thinking about just doing a 90% water change with the new salt.

[markalot]

What calcium test kit are you using? Are you doing all testing at the same time every day? With high usage you will want to dose small amounts hourly, not twice a day.

[Oceanus]

I am using all Salifert kits except my new API pH kit. I generally test between 1 p.m. and 3 p.m. every day. My pH was at 8.4 this afternoon, so I think switching to bicarbonate may be a wise choice.

 

I am going to order a reefkeeper lite and try to break up the doses into multiple doses a day. Thank you!

[farkwar]

http://s1078.photobucket.com/user/RichardSperry/media/solpre.jpeg.html'>

[Oceanus]

Quick update:

I'm still seeing some small 1x1" or 2x2" spots of precipitate forming on the glass over the course of a few days. My alk is stable around 8.5dKH and my corals are all doing well. However, I am still suffering from low calcium: it's hanging around 225ppm. I have been doing some more water changes with the H2Ocean and it is helping with the precipitation issue it seems, but after a few days calcium is back at 220ppm~ish. My lFS suggested that my Supermarket RO/DI water might be treated with a softener before going through the membrane and the softener may remain in the water. Does this seem plausible?

[Amphiprion1]

Quick update:

I'm still seeing some small 1x1" or 2x2" spots of precipitate forming on the glass over the course of a few days. My alk is stable around 8.5dKH and my corals are all doing well. However, I am still suffering from low calcium: it's hanging around 225ppm. I have been doing some more water changes with the H2Ocean and it is helping with the precipitation issue it seems, but after a few days calcium is back at 220ppm~ish. My lFS suggested that my Supermarket RO/DI water might be treated with a softener before going through the membrane and the softener may remain in the water. Does this seem plausible?

 

??? The byproduct of a softener is usually just sodium ions, so fairly implausible. Have you tried halting alkalinity dosing to see how it behaves? Once you have an idea of how alkalinity is used, I would begin dosing calcium only until within reasonable ranges. Once there, start with 25% or so of the alkalinity supplement and test/observe to dial in dose. If you find parameters fall out of line while experimenting, perform a water change

[Oceanus]

Hmm this is interesting, I think I will try halting alk dosing and just dose calcium until it is back until 400~ppm. I can't start that right now though because I am leaving this weekend, so I'll do this early/mid next week.

I did have alk falling rapidly when I was dosing only 20ml~ per day, and it would sink to about 6.1dKH. I upped it to around 33ml pre day and it has been holding around 8.4~...