Sand filter and broken lateral

[saygig]

Last summer I noticed sand in my pool by the input valve. I was informed it was most likely a broken lateral. The pool shop says it's a tough job to do and I should have them do it. My husband is pretty handy and thinks he can take care of it. Can someone tell me if this a do it yourself job or a hire job. thanks.

[matt4x4]

This is an easy one!
First, if it's 3+ years old, replace the sand while you're at it (might as well get Zeobrite as a replacement).
Remove multiport valve by undoing all bolts where it joins the filter.
If the sand or medium is fairly new, you may want to save it by removing it into a clean container or containers, some will have to be washed out with the filter on it's side to get it all out.
NOTE: Wet medium is going to be tougher to put back in than dry medium.
Once the sand's gone, you'll see the laterals pointing out like a star in the bottom, you can lift the tube some, reach in and unscrew them one by one, inspect them and replace the broken ones, I believe they're relatively cheap and you may want to replace them all since they get brittle with time.
Since you know your filter brand and size you should be able to pre buy them before starting the job so the system is only down for an hour or so.
If you don't want to replace them all (usually 6 pcs - your diagram may be available on-line), at least buy 2 or 3, that way if you have one left over it can be a spare for when you have to do it again.
Put everything back together in reverse order.

[saygig]

Thanks for the advice and help. The previous owners actually left the filters manual so we have all the info we need. Thanks again.

[Poconos]

Heh Heh !! Matt didn't mention that getting the sand out can be a dog. I have a 300# Hayward and used a shop-vac to suck the stuff out after draining the water. A dog because you have to dump the vac often as it gets heavy real fast. The laterals on the Hayward folded so you can remove the entire center assembly. When you put the sand back they recommend filling the filter halfway or so with water so dumping in the sand won't stress the laterals.
Al

[waste]

I clearly recall putting 'pea gravel' into any sand filter, up to about 1/2" to 1" above the laterals before adding any sand. Al is certainly right about having water in the filter before adding sand (and, as I suggest, 'pea gravel'). Perhaps it's because adding the pea gravel might hide a broken latteral. However, I recall the PacFab Triton (?) filters recommending doing this.
This makes sense, the top 12 - 24" will catch as much "stuff" as an extra 1" (or so) will, and you get a less constricted flow around the latterals. (And if a lateral breaks the sand into the pool will be lessened, perhaps allowing the owner to postpone a lateral replacement a season)

[duraleigh]

Interesting. I talked to the Triton folks when I filled my TR-140. The instructions called for pea gravel as well but were VERY unclear as to whether it was essential.

My end result was to not use the gravel. No one could tell me it was essential in a way that convinced me. The pros in my area (I called three) don't use it and two hadn't heard of it.

I sorta' ended up thinking the sand filled around the gravel very quickly, not doing much to alter the filtering characteristics.

This is not to dispute "Waste's" thinking but simply to post how I arrived at a different conclusion....I have no idea if one makes more sense than the other.

Matt, You finally found a scenario where I agree with replacing the sand :D :D (We've discussed that before, I think) It would be such a hassle to salvage and reload the old sand.......new in the bag makes more sense.

Al, my good ole' Triton has a clever valve on the bottom that allows you to release only water or both water and sand. My assumption is that in the "sand" position it would allow you to wash the sand out with a hose....seems like it wouldn't be too bad but I've never tried it. Am I missing something?:confused:

Dave S.

[waterbear]

Putting a layer of corse filter mateial (pea gravel) in befoe the fine filter material (sand) is an effective way to filter and is pretty much standard in any aquarim filter setup. The sand will not "fill the holes" but will pretty much stay in it's own later. This will allow a better water flow through the laterals with less chance of them plugging with sand, will help reduce the chance of lateral breakage, and should give you more effecient filtration overall. It probably is not necessary but IMHO is a good idea. I am wondering if anyone has ever done it both ways to check the difference in a pool filter. BTW, sand filters similar (sometimes identical) to pool filters are used to filter large commercial aquariums for mechanical filtration.