Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 4 of 4

Thread: No drains - do you need additional skimmer

  1. Back To Top    #1

    Join Date
    Mar 2016

    No drains - do you need additional skimmer


    This is my first post and my first question - lots of info on the forum

    We are installing 18x36 in-ground pool (20000 gal, 613 sq. feet) with Hayward EcoStar Variable Speed Pump.
    The pool will have no main drains as stated by the PB.

    Here are my questions, based on the above specs:
    1. How many skimmers should there be? Is more needed since no drains?
    2. How many returns should there be?
    3. 1'5'' or 2' pipes?


  2. Back To Top    #2
    Nectarologist's Avatar
    Join Date
    Apr 2015
    New York

    Re: No drains - do you need additional skimmer

    A pool that size I'd want 2 skimmers with a main drain so maybe tell them 3 to circulate more water? It still won't circulate the deep water well though. That being said I have serviced pools with one skimmer and no main drain and they seemed ok (basically really old concrete pits). I assume a main isn't possible for some reason right (not that the PB just doesn't want to do it)?

    My pool is a bit smaller (16x32) and I have 5 returns coming off 3 main return lines. The feed that goes to the stairs splits to 2 returns and the feed that goes to my bench splits to 2 with another independent run to the wall. I have no issues. Can't help on the pipe size, sorry.
    Inground, vinyl liner, 16 x 32 (approx. 21k gallons), roman end w/ bench, 2 Jandy LED lights
    Pump: Jandy Flopro, 1.5 hp Heater: Raypak, 266k btu (P-R266-A-EN-C; nat gas) Filter: Jandy C340 (cartridge filter) Robot: Doheny's Dolphin Discovery SWCG: Circupool RJ45

  3. Back To Top    #3
    Mod Squad pooldv's Avatar
    Join Date
    Aug 2012
    DFW, TX

    Re: No drains - do you need additional skimmer

    Welcome to TFP and congrats on the new pool!

    1 skimmer in the right place is enough, 2 is better. Make sure they are downwind in fall #1 and spring #2 to work best. 3-4 returns is good. 1-1/2 pipe is good, 2 is better.
    TFP Moderator
    If TFP helped you or saved you money - Become a TFP Supporter! <--Click here
    2012 build and pics, 20k gal gunite, black onyx pebblesheen, OK flagstone, IntellifoVS, cart filter w/Pleatco, IC40 SWG, Solartouch, 5 12'x4' solar panels, HP50HA heat pump, 8mil solar cover, borates, TF-100 test kit, SONOS, Doheny's Discovery Robot, hot tub on bleach

  4. Back To Top    #4
    mas985's Avatar
    Join Date
    May 2007
    Pleasanton, CA

    Re: No drains - do you need additional skimmer

    Main drains are not necessary to keep a pool clean and well sanitized. APSP, has done a study on MDs and came to this conclusion some time ago:

    Since MDs don't really add much to the circulation and sanitation of a standard pool, the skimmer placement and return placement should not be any different than a pool with MDs.

    2 skimmers may or may not be better than 1. It depends on which way the wind blows. I have 2 skimmers but I could easily get away with only one as most of the debris ends up at the skimmer in the deep end.

    Also, with 1 skimmer and a VS or two speed pump, you can usually run at lower RPM than if you have two skimmers since you are splitting the flow rate between the two skimmers. So if you can get away with one skimmer, it can actually save in energy costs.

    Also, since I use a pool cover most of the time, the skimmers are pretty useless until I remove the cover.

    For returns, I would have at least 4 and all 2" pipe. For suction side, I would go with 2.5" pipe for a single skimmer or 2" pipe from skimmer to pad if two skimmers.

    Returns are far more important for distributing chlorinated water back to all parts of the pool so just make sure they are equally spaced around the pool.
    Hydraulics 101; Pump Ed 101; Pump/Pool Spreadsheets; Pump Run Time Study; DIY Acid Dosing; DIY Cover Roller
    18'x36' 20k plaster, MaxFlo SP2303VSP, Aqualogic PS8 SWCG, 420 sq-ft Cartridge, Solar, 6 jet spa, 1 HP jet pump, 400k BTU NG Heater

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts