Return pump seized for 3 days... Can I replace impeller?

[nerdz]

Came home to a high salinity, 68 degree display tank...

Some fairly heavy coral/fish losses.

Anyways, pump was plugged in and not spinning for 3 days. Impeller was seized with calcium. Will main body be okay, or do they burn up?

Its a Mag5 and I cant get the shaft out of the magnet. If body will be alright, I'll pop down to JLs for a new impeller

It was pretty fun watching my wifi controller on vacation show temps creeping up to 87 degrees. I guessed:

-heater stuck on
-MH stuck on
-ATO failed> sump ran dry
-Fried pump raising temps
-failed return pump

Turned out the be the return pump.

Lots of fun things to ponder over the last days of my vaction!

[sphelps]

Should work with new impeller but no guarantees.

[SeaHorse_Fanatic]

Bring the whole pump to J&L. If you can't get the impeller out, then no point buying a new one. See if they can help.

[sphelps]

I believe it's the shaft and impeller he can't separate.

[asylumdown]

Soak the shaft and the impeller in some vinegar overnight, it might be enough to get them apart. I'd also check all your other pumps. The precipitation reaction that fried this pump will be tank wide, so there's a good chance the rest of your equipment is at risk for the same thing. This same thing happened to me once, and while it was my return pump that failed, I discovered how close to failure my skimmer pump, both Vortech's, and reactor pumps all were when I took them apart too.

Unless it's been many years since you cleaned your pump, enough calcium precipitation to fry it usually means something is off with how you're dosing. Is your mag extremely low/are you dosing too much/dosing calcium and alk in wildly different ratios?

[nerdz]

Originally Posted by sphelps

I believe it's the shaft and impeller he can't separate.

Thats correct, impeller comes out of body. Inner ceramic shaft is seized inside magnet.

I was able to push out the shaft using a clamp and a small rod as a drift. Man, was it welded in there!

Scraped off all the rock-hard build up with a razor. Pump is currently running fine. If it to works I for the next few days I'll replace the impeller.

Cheers

[asylumdown]

it's a much better idea to put it in vinegar. Even with a razor you won't have gotten it all, and the CaCO3 that gets left behind is like a magnet for more precipitation. On a smallish impeller and shaft like that, 45 minutes in regular old table vinegar would leave it sparkling and 100% free of any calcified build-up. You should do the same with your skimmer's impeller, and any supplementary water moving devices you have elsewhere in the tank, making sure to completely disassemble any parts that move against one another first. You will probably be surprised at how many bubbles start rising off things you didn't think were coated in precipitation.

[nerdz]

Originally Posted by asylumdown

Soak the shaft and the impeller in some vinegar overnight, it might be enough to get them apart. I'd also check all your other pumps. The precipitation reaction that fried this pump will be tank wide, so there's a good chance the rest of your equipment is at risk for the same thing. This same thing happened to me once, and while it was my return pump that failed, I discovered how close to failure my skimmer pump, both Vortech's, and reactor pumps all were when I took them apart too.

Unless it's been many years since you cleaned your pump, enough calcium precipitation to fry it usually means something is off with how you're dosing. Is your mag extremely low/are you dosing too much/dosing calcium and alk in wildly different ratios?

Thanks for your input.

Yes, running dosers now and think you may be right about the precipitation. Also my 2-part dumps in a small camber of my sump were the return pump is... I'm wondering if this temporary high concentration is contributing to the build up?

Anyways, tank is a mess after this failure 9 days into my vacation. I'll have to reevaluate my doses and check over the rest of the equipment.

[nerdz]

Originally Posted by asylumdown

it's a much better idea to put it in vinegar. Even with a razor you won't have gotten it all, and the CaCO3 that gets left behind is like a magnet for more precipitation. On a smallish impeller and shaft like that, 45 minutes in regular old table vinegar would leave it sparkling and 100% free of any calcified build-up. You should do the same with your skimmer's impeller, and any supplementary water moving devices you have elsewhere in the tank, making sure to completely disassemble any parts that move against one another first. You will probably be surprised at how many bubbles start rising off things you didn't think were coated in precipitation.

After the shaft was scraped clean with a new razor blade I gave it the vinegar treatment.

[asylumdown]

Originally Posted by nerdz

Thanks for your input.

Yes, running dosers now and think you may be right about the precipitation. Also my 2-part dumps in a small camber of my sump were the return pump is... I'm wondering if this temporary high concentration is contributing to the build up?

Anyways, tank is a mess after this failure 9 days into my vacation. I'll have to reevaluate my doses and check over the rest of the equipment.

oh yah, that's definitely a possibility! Does your doser wait any amount of time between dosing? I'm using a profilux doser for my Alk, mag, and calc and it's supposed to be programmed to wait a healthy amount of time between dosing alk and mag, but sometimes it seems to dose them one right after the other. I've noticed on a couple of occasions that the pump for one seemed to start spinning before the pump for the other had even stopped. Depending on how turbulent the water is and how quickly it's changed over in that chamber, I can see that potentially causing problems. Even if it's spacing the dosings far enough apart, it's possible that just the act of adding one of the elements to a confined space like that is enough to momentarily alter the concentrations enough to drive a localized precipitation reaction with the elements that are already in solution. It would depend on how big that chamber of water is relative to the concentrations/volume of dosing solution being added and how quickly that water is turned over. At least you'll be able to tell pretty conclusively which it is by looking at your other equipment.