DIY Skimmer

[aaron]

I am mid way through building a skimmer and after looking at a lot of designs online i decided that i should make mine able to be dis-assembled so i can pull it apart clean it periodicly. What i need to know is -
1. what do you call those nylon screws that hold the sections together ? WEDFR uses them on his diy skimmer shown on the photo gallery of this site.
2. how do you attach them? do you have to tap a thread into the bottom piece of acrylic?
3. where in NY can you buy them?
4. what do you use for gaskets in the joins?
Any other advice on this aspect of skimmer construction would be appreciated.

 

[wedfr]

hi aaron, They are called thumbscrews. Knurled head nylon thumbscrews to be exact. To attach them the bottom piece of acrylic does need to be tapped unless you get some wingnuts but i recomend tapping the acrylic.

I use orings for seals. both the orings and the thumbscrews can be ordered form mcmaster.com and you will have them the next day since they are in NJ.

I dont know of any local place to get them

What tpe of skimmer are you building?

 

[aaron]

I'm building a biggish venturi skimmer - using a powerhead to chop the air and water together. I'm basing the design on an old skimmer i used to have - "The big Mombasa" i dont remember who made it but it is still powering away in australia six years later. Ive just made mine a bit bigger / taller and i'm using a bigger powerhead.
Do you use a router to cut out a rebate channel to seat the o-ring on each flange face? or do you just sort of put it in place and screw it together?

 

[aaron]

Hey Wedfr,
thanks so much for the info. I just have one more question: What size thumbscrews are they (I dont really understand the sizing on the website) ? I mean what thread diameter? everything is listed as #10-24 or something similar.
Thanks again for your assistance.

 

[wedfr]

i use 1/4-20 its a very popular size, the 10-24 i think will be too small and snap on you.

Youll need a #7 drill bit for the pilot hole and a 1/4-20 tap

 

[wedfr]

so hows it goin , did yu finsih? i wanna see what you came up with and howit came out

 

[aaron]

I finished it last weekend. still havent powered it up yet but i should get it going later today. Thanks for all your help, Mcmaster is the goldmine for DIY! I had a guy who was going to charge me $25 in manhattan for a gate valve and i got it from them for $8.
There's a picture of it nearly finished.
http://www.manhattanreefs.com/cgi-bin/album.pl?album=00000369
I'll post some more when i get a chance

 

[FRY]

looks great good job,how much did it cost you

 

[aaron]

I guess it was about $50.00 -
$30 worth of acrylic and about $20 worth of other bits and pieces. The current configuration is fundamentally flawed though. I fired it up today and with the straight down drain in the bottom of the riser the water just spiral straight down and out. I need to put a fitting in to break this direct route out of the riser to give the bubbles a chance to rise up. It currently looks like a tornadoe of bubbles that never rise up the tube. I figure a mushroom type cap over the drain should do it.

 

[aaron]

I just fitted the cap over the drain and it's working perfectly - no scum yet as it is running on my half set up 50 gal. I'm getting some new LR this weekend so that should test it out nicely. I might put up a couple of "scum" pics when i get the chance - I know what turns you guys on

 

[FRY]

hi aaron
hows the skimmer doing you have a picthure of it

 

[aaron]

Hey fry,
no, No pictures yet.
Once i ran it with the sump at its correct level i'm having problems with the venturi, I think there's too much head pressure for the pump to suck down the air into the impeller, I think i'll either have to reposition the pump or get a bigger pump.
I'll let you know how things go - i must say while DIY does save money its not the quickest solution

 

[wedfr]

DIY can save money but in a lot of cases you end up spending the same and usually more to correct mistakes youve made or redoing a project. And yeah it takes lots of time. Let us know how it finally works out

 

[aaron]

Well, everything is fixed and running nicely now, all i had to do was raise the powerhead up in the sump a bit so i could suck in the air into the venturi.
No bioload in the tank at the moment so i'll have to wait until i get some live rock before there is anything exciting happening in there.
I did post a couple of pictures of my tank in sydney though.

 

[FRY]

hi arron

hows the skimmer doing

 

[aaron]

I'm still tweaking it - i want to have it working really nicely before i post pics. After running it for a couple of weeks it would seem that it really needs a bigger pump to push a bit more air into the reaction chamber- at the moment its not bad but its having trouble pushing the foam up the riser and into the collection cup.
currently i'm using a rio 800 but i think i could use something like a 1400 its just a little hard if you dont have one lying around - I dont want to buy one and find out that its either too big or not big enough after a have drilled the venturi holes in it. I have a 2100 but i think that might be over kill.
I have been building a stand and light hood for two other tanks so i havent really had the time to do much on it in the last couple of weeks.
I'll update soon

 

[wedfr]

give the 2100 a try, im sure it wont be too big. HAving the air being sucked in really cuts down on their power