July Update - First fish in the DT, and more exploding filters!
July Update - First fish in the DT, and more exploding filters!
Relatively quiet couple of months. Mostly just tending to the QT tanks, with a few bits of excitement thrown in to keep things interesting.
Since Last Update:
- 2 Batches of fish released from QT to Display
- Third round of QT halfway stocked
- Corals not thriving in QT; none relocated to display
- Washer and Dryer finally hooked up
- HVAC Issues
- Second RO/DI cannister exploded. And then a third canister
- Soda ash overdose locked up both Abyzz pumps, Hydro Wizard, all 5 Tunzes
First two batches of fish released from QT into Display
Completed 2 rounds of QT. Display tank now has the following livestock: 17 green chromis, hippo tang, sailfin tang, yellow tang, fox face lo, 4 cardinals. One loss: a fancy blue damsel found his way through a gap in the overflow egg crate where I had cut out a little too wide around the Hydrowizard bracket. Found him in one of the sump filter socks.
One thing I've found interesting with this first batch of fish is that the 4 big fish tend to hang out together, 'schooling' moreso than when I've had groups of 4 to 6 tangs of the same species in smaller tanks. They also seldom swim higher than the bottom 1/2 of the tank. I assume this will break up and they will behave more normally as the tank becomes more stocked.
Tank is still comically empty, but at least there is a little motion in there now.
Round 3 of QT Currently 1/3 stocked
In QT 1: Chocolate Tang, Blue-eyed Kole Tang
QT 2: Empty. 4" Naso died after 10 days of QT. Started Paraguard on day one and this seems to have stressed him: was eating well in the store, okay on day one in QT, then very anemically for remainder of his time. Going forward, will stick with the approach used for the hippo tang, which was to delay starting Paraguard until he was eating vigorously and taking pellets. The hippo broke out with a serious case of flukes after 10 days-- looked like a shag carpet-- but was healthy enough that he bounced back from a freshwater bath and week of Paraguard. Perhaps the Naso would have died no matter what, or perhaps he would have weathered the parasites and Paraguard if I'd let him build up some strength first.
QT 3: Not serving as QT. Currently has a few favorite soft corals, anemone, maroon clown, lemon peel angel, purple dotty back.
QT 4: Flame Hawk
Next up for QTs 2 and 4:
- 4 Pyramid Butterflyfish
- Naso Tang
- More Chromis
Skimmer at work
The big MRC skimmer is finally doing something now that there are a few fish in the display. As can be plainly seen in this pic, I haven't yet connected the waste cup float switch to the controller. Need to get to this soon now that are fish in the system!
Corals not thriving in QT
Not yet moving any corals into the display as I'm not happy with the state of the coral QT. Most of the corals have bleached significantly, so there's something I haven't sorted out properly. Parameters have seemed good: Alk between 6 and 8, Ca 450 - 550, Nitrates zero, Phosphates .03. The big differences with this QT system versus my previous systems are: 1) LED lights, 2) almost no fish load; 3) higher temperature
The bleaching started before the HVAC problems led to higher temps, so I most strongly suspect the lighting or the absence of food.
Over lighting is an obvious candidate with four 100W pendants over a 16" deep 3' x 4' tank. But the pendants are dialed back to 40%, and PAR meter readings at the bleached corals are only 120 to 220. That said, most of the happier corals have been on the bottom or in shade.
Starting 2 weeks ago I dialed light intensity back to 30%, moved several of the corals that were on the egg crate stands down to the bottom in shade. Suspecting low nutrients as another possibility, I also started supplementing amino acids and food. I've never in the past dosed food or amino to keep my corals happy, but I've always had a healthy fish load and plenty of food going into those other systems.
Between the lighting and food changes I think there may have been some improvement in coloration; still a bit early to tell.
HVAC Problems
Our HVAC engineer seems to have missed the mark on this system, as it has not been keeping up. Temperature in the room creeps up from the 75F set point to 80 during the day. This has in turn resulted in higher tank temps of 79 to 83. Very frustrating as I gave the engineer all of the equipment load details, and asked him to spec the system to be able to handle an additional 10,000W of incandescent lighting in the event that the LEDs didn't work out.
It does seem like there should be sufficient cooling with 3 in-room units fed by a 3 ton condenser that is shared only with one other room, the 300 square foot projection room for the upstairs media system. But it is confirmed to be a design issue as the installers have verified that coolant levels, air flow rates, and output air temps are as expected,
Next step: getting a quote from the HVAC company to add a 6th condenser and additional wall unit in the fish room.
RO/DI cannister exploded again. And a third time
2 weeks after replacing the first canister that blew out so spectacularly, another canister in the pre filter section failed. 10 days after that, the 3rd canister failed, though I caught it a bit earlier while it was spraying more like an outdoor misting system rather than a power washer fan nozzle. Fortunately, I had ordered 2 replacement canisters after the second failure, so this was a relatively quick fix.
A fine example of southern engineering
The middle canister blew when both reservoirs were nearly empty, so I had to rig up a temporary solution while waiting a week for the replacement to arrive. First, pulled the cannister and moved one of the DI canisters up to the pre filter section. Next, glopped on huge quantities of PVC glue along the vertical stress cracks of the failed canister. No adhesive will stick well to the PE material of the canister, but it was good enough to only leak slowly after I transferred that canister to the low-pressure DI output side. I then needed to route the roughly 1/4-gallon per minute leak over to the sink. The trash bag itself wouldn't hold form to do the routing, thus the plastic storage drawer with 2 holes drilled in the bottom. This lovely contraption held together for the day it took to refill both reservoirs.
Exploding canister problem solved?
Three failures in short order made it fairly obvious that I was doing something wrong. On further thought, I realized that my safety cut-off, combined with infrequent running may have led to the problem.
Back when I first set up the filter, I left it connected to city water and powered on 24x7, relying on its built in actuated ball valve and controller to stop the water flow. I noticed after a month that there was a slow leak in the fittings near the actuated valve. Redoing that plumbing looked too challenging as it is surrounded by assorted controller bits and wiring, and everything is tied down or bolted to the backboard, so I decided to instead just start turning off the water supply at the wall when not running the filter. For the first six months of running the system, prior to moving the first fish into the display, I was only doing automated water changes of about 10 gallons (2gal per QT), so I could go almost a month between needing to run the RO/DI filter.
My hypothesis is that with 21+ days between filter runs, bacteria were growing in the pre filters. It seems likely that this bacteria growth was creating gas pressure with nowhere to go, similar to the way a canned food that goes bad can swell the can containing it. In normal operation, with the city water supply valve open at all times, as bacteria grew and outgassed, it could 'burp' its way back up the city line as pressures started to exceed the ~60psi coming from the city. In my setup, though, there were closed valves on both ends, so pressure could build right up to 85psi failure point of the canister.
The solution-- assuming this hypothesis is valid-- was to put a pressure relief bypass on the city supply line. Now, after a filter run completes and the city supply valve is closed, I then briefly open this valve which bleeds off the water pressure and drains back into the sink. I also briefly reopen and close it every week or 10 days. There is a small burst of pressure each time, which would seem to lend some credence to my bacteria growth hypothesis.
Soda Ash Overdose
Decided to switch from Sodium Bicarbonate dosing to Soda Ash because pH had been creeping down, ranging during the day from 7.9 to 8.2. Unfortunately, forgot that I had bumped the Alk dosing level when I ran short of baking soda mixing the previous batch. As a result, over the next 18 hours 6 liters of fully saturated Soda Ash solution were added to the system. On the one hand, 6 liters is a lot of soda ash, but on the other hand it is a 2100gal water volume, so how bad could it be? Turns out, pretty bad.
On the bright side, pH was a robust 8.3 the next morning, and all livestock were happy. Not so great: every pump except the 3hp Pentair was locked up: 2 Abyzz 420s, 1 Hydro Wizard ECM-63, 5 Tunze Stream 6300-series.
Further, the glass was completely hazed over with a precipitate of the same consistency and tenacity as about 2 years of unchecked calcareous algae. And I speak from experience regarding the calcareous: in the previous tank, a 2' x 2' patch of back glass grew calcareous unchecked, and cleaning this precipitate off took the same level of effort. Key difference being that instead of dealing with 4 square feet of glass, this time it was roughly 140 square feet. This took several hours of the hardest manual labor I've yet put into aquarium work. Yuck.
Precipitate haze remnants
Remaining haze near the edge where the magnet isn't as effective. This is what the entire tank looked like before cleaning.
Back on the pumps, this may turn out to be the single costliest mistake I've made yet. I got one Abyzz and the Hydro Wizard back on line after cleaning, but both are now making noises that they did not previously. The Hydro Wizard in particular sounds like it may vibrate to pieces. It is back off line while I contact support to see if I can send it back to them for repair. One thing I learned about the Hydro Wizard is that it is not user serviceable for anything except replacement of the propeller blade. The rotor and bearings are sealed in the housing, so the only way to clean it is to run the pump in a bucket of vinegar solution. I suspect that its bearings are frozen to the rotor shaft, rotating against the housing and starting to come apart. The Abyzz noise is less scary-- it is a brushing sound rather like rubbing the smooth side of 2 credit cards together-- but still concerning as the pump was previously so silent that I would have to put my hand on it to verify it was running.
The other Abyzz pump is a complete mess at this point. The soft iron bearings were frozen to the rotor shaft so firmly that even 36 hours of soaking in vinegar could not break them free. I ordered new bearings, (which Abyzz was extremely quick to deliver), but then in the process of breaking the bearings loose, they were so severely stuck that the rotor shaft which holds the impeller broke free of the magnet body before the bearing broke loose of the shaft. I'm awaiting an answer from Abyzz as to whether they can repair the rotor or I will have to guy a new one (which I expect will cost significantly more than any other entire pump I've purchased). Fortunately, I had a spare Abyzz A200 that is sufficient to feed the skimmer for now.