[Viridis]

Messing around on sketchup the other day, and started designing a growout/fry rack. Not completely sure what size bins I'll use, so I just used the closest sterilite I had lying around for reference. The blue line is the "new"/filtered water, and the brown is the waste. The plan is to tap the PVC tubes above each bin and have the valves from jehmco with airline running to each bin. Each bin will be drilled with a uniseal in the back, and will have a 90° elbow act as an overflow, leading the "waste" water down to the sump. The plan is to mainly use this for growing out crayfish; though I'm sure I'll probably use it for fry at some point as well.

What do you guys think of this setup (sans container/tank size as that hasn't been decided yet)? Do you think it'd be a good idea to add drippers to each line in addition to the valves, or are they more than enough?

crayfish rack coloured.png

[Meep]

I'm personally not a fan of drilling (or cutting) cheap plastic bins, they have a tendency to 'split' where you cut them over time...

I know it might cost a little more but if you want to avoid glass, may I suggest you look at clear steam table pans...

The 'generic brand' 8" deep ones should work well, I would also consider bottom mounted overflows that way you can more easily maximize and adjust the depth of the water...

http://www.webstaurantstore.com/5116...th:6~8*-inches

Also with the steam table pans you can get nice drop on lids that are easy to remove and work with... The ones with that 'spoon handle' cutout give you a place to insert the fill line without additional cutting...

http://www.webstaurantstore.com/1-2-...PLPA7120S.html

Of course those are just my options, nothing inherently wrong with your design as long as the main upright drains are sized big enough to handle the overflow...

[Viridis]

I did not think of polycarbonate tubs; that's a great idea!!! Still cheaper than glass (even using tiny glass tanks, I could build 3 of these racks for the price of just the tanks), and far more resilient than the sterilite. I'm definitely considering those now.

re bottom mounted; I agree, however because these will mostly be used for crayfish, I want to keep as much floor space available as possible. And though a tube won't take much space, it's that much less floor space in an already smallish tub, hence drilling the back.

As for big enough drains, I was planning either 1/2'' or 3/4'' for them. Do you think 1/2'' is enough, or should I go with 3/4'' just to be safe? The price difference is negligible (same price at Lowe's for connectors).

[Meep]

The drain size will all be dependent upon how fast the fill is, what you want to avoid is and backwash into lower tanks... If the drain line isn't sufficient then the overflow from the top tanks will start to fill the bottom tanks and then all %#$^$&$ happens, worst case flooding, bad case the lower tanks are flooded with 'stale' water from the top tanks... Even with bigger pipes you could get a siphon lock, best to drill a hole at the top of the vertical overflows, or use a T at the top and just leave it open as a vent stack...

Another nice thing about the steam table pans is that they are an industry standard size... So unlike 'plastic tubs' like Sterlite and Rubermaid that are constantly changing sizes and designs, if you ever need to replace a steam table pan the new ones will fit right in as they are standard sizes... Plus you can get real fancy with the rack design using steam table pans say 1/3 pans on top, 1/2 pans in the middle and full pans on the bottom, all the same 'width' but different depths, or switch them up other ways... Or link them together for different configurations, two 1/2 pans or three 1/3 pans is exactly the same size as a full pan so you can mix and match in a standard rack size...

[Viridis]

Ahh, that's a good point, I did not think of that. I'll make sure I go with T's on top.

Very good point about the polycarb bins. I do like the more rigid plastic as well. And swapping them out is definitely a plus.

The drain size will all be dependent upon how fast the fill is, what you want to avoid is and backwash into lower tanks... If the drain line isn't sufficient then the overflow from the top tanks will start to fill the bottom tanks and then all %#$^$&$ happens, worst case flooding, bad case the lower tanks are flooded with 'stale' water from the top tanks... Even with bigger pipes you could get a siphon lock, best to drill a hole at the top of the vertical overflows, or use a T at the top and just leave it open as a vent stack...

Another nice thing about the steam table pans is that they are an industry standard size... So unlike 'plastic tubs' like Sterlite and Rubermaid that are constantly changing sizes and designs, if you ever need to replace a steam table pan the new ones will fit right in as they are standard sizes... Plus you can get real fancy with the rack design using steam table pans say 1/3 pans on top, 1/2 pans in the middle and full pans on the bottom, all the same 'width' but different depths, or switch them up other ways... Or link them together for different configurations, two 1/2 pans or three 1/3 pans is exactly the same size as a full pan so you can mix and match in a standard rack size...

[Stryf]

Did you try out the bins, if so how did they work? Seems like an interesting idea.