So, I had a catastrophic burst of my pipes today. The problem started with my pump not pulling water from the pool. Having had this problem before, I started my troubleshooting: pump and motor working; impeller is in working order; nothing clogging the impeller; strainer basket in pump clear; nothing blocking/clogging the pool inlet (to the pump). This tells me the pump is sucking air. I remove the strainer cover and notice an odd back spray coming from near the impeller (as though there is a crack in the internal part of the pump housing, sort of like a cracked engine block that doesn't seep liquids out of the housing, but leaks back into the housing). Then, I notice that the screw in fitting to the pump (the outlet) is loose and slightly leaking water [attachment=2:53srhq16]outlet1.jpg[/attachment:53srhq16]. This is something I just had repaired and SHOULD have called the person who did the repair (but, I didn't--AHA, I can fix it myself--and, usually can). So, I cut the pipe, and discovered I was able to turn the fitting several turns by hand. After hand tightening the screw in fitting then wrench tightening it, I go to use a PVC coupling to repair the PVC pipe I cut, ONLY TO DISCOVER the outer diameter of the PVC pipe is slightly larger than the standard 2" couplings available in my local big box DIY store. Since I couldn't find the correct diameter pipe coupling, I bought a temporary rubber gasket-- you know, the one that says "for drain use only"-- and installed it. With my pipes repaired (temporarily), I turned my pump on. Again, pump is in working order but not drawing water from the pool. My next step was to double check to make sure there isn't an obstruction in the inlet going from the pool to the pump. Using a water bladder connected to a garden hose, I inserted the hose into the inlet and turned on the hose with the pump running. About 1 minute later, my pipes explode. I recognized a few things (duh): 1- I should've called the pool professional; 2- don't use rubber gaskets; 3- I should've called my pool professional. But, what I really need to know is, "what happened?" The pipes exploded at two different elbow, not at the rubber gasket. A few facts: this pool is at least 20 years old (I am not the original owner of the house); the filter is a sand filter; whisper flow pump, triton sand filter, and motor are all at least seven years old (the motor was replaced the first year I owned the house- about 7 years ago); there is no obstruction from the pool to the pump (using the garden hose and bladder, I pumped water from the pool to the pump); I HAVE NOT determined if there is an obstruction going into the filter, but I find that a likely explanation (after backwashing, I drained the air from the filter, but once the air was drained, no water spurted from the valve. This tells me either there was an obstruction or air was leaking into the filter). I'm considering replacing the entire system (new filter, pump, etc...). Costly, yes. But, I won't pursue this drastic measure unless I feel it is an absolute must. I can really use some help...oh, and yes, my pool professional will get a call today. But, I still need to know what I did wrong and what is the probably cause of the pump not pulling water from the pool.