iwaki pump going bad?

[alteredego]

I bought a iwaki pump used, it flows 2400gph. I am using it on a losed loop system only. Today it started shooting what looks like smoke out of the return. this turns out to be very timy bubbles. At first thought it could be an air leak, so i shut the pump down for a few hours to find the leak. I found no leaks. is this a sign of a seal going out? It kinda sounds like maybe a bad bearing. I've only had this pump running for a few days, and i notice a diffrence in sounds. If i leave the closed loop off this week while i'm on tdy, will my fish only be effected badly? my wife knows very little about the tank so i going to running off of luck this week. I went ahead and threw every small pump i own in the tank, but being a 10' 400g it doesn't create much flow.
please help.....

[Ram_Puppy]

Personally, I say why risk it? Since your going to be gone get a Reeflo Dart or another great pump locally and switch it out.

If the iwaki is not bad, you just got yourself a water change pump/spare/backup.

You have obviously invested a lot in a 400 gallon tank, the cost of a new pump is potentially less than the ramifications of a system failure.

[alteredego]

true, but i leave tdy at 0600 in the morning, as you can tell i'm worried about since i'm still up monitoring the fish. how can something so relaxing be so nerve racking.

[GaryP]

I have a sneaking suspicion that the O-ring on the pump head is bad. That could be what is allowing the air into the pump. That's easy to check. When was the last time your broke the pump down, cleaned it, and inspected the impellor?

[matt]

I never heard of an iwaki that runs anything close to 3400gph, but that doesn't mean it's not so...you can try calling iwaki walchem. I believe they're in boston, but you can check the website and get a phone number. The technicians there are very knowledgable and helpful with problems with their pumps. Gary's idea of taking it apart and cleaning is a good one, if you bought it used and have never cracked it open you never know what's in there.

[alteredego]

very true. i should have broken it down when i first bought it, and replaced at least the rubber disposable stuff. i guess i got in a hurry to get the fish into the 400g because the 125 was getting over stocked. do you think the closed loop being down for three days will hurt the fish? I am now in GA and there is nothing i can do until thurs. My wife says she will turn on the pump for short times in the evening to circulate some water, although the racket the pump makes may stress out the fish.

[captexas]

Not sure what other filtration you have on such a large tank, but if this is just the closed loop pump that is acting up, the fish should be fine. Usually a closed loop system is to increase water flow for corals, not for the fish. As long as you are getting some water movement and/or surface agitation for gas exchange they should be fine until you get back home. As long as your main filtration takes care of the wastes, the main concerns then for fish are oxygen and temperature.