from DHaut's 40 thread
I just acquired a 40B and I would like to do a corner overflow with herbie-style drain and a back return.
I've briefly looked here: http://www.nano-reef...p;#entry2890605
1. What size holes do I need for the drain and the backup?
2. What size hole for the return?
3. What pump recommendations? (I'll be running an MP40 for the main tank flow)
4. What plumbing parts do I need to pull this whole thing off and where's the best place to get them?
I'm a total noob with tank plumbing, so any help is appreciated.
What size holes do I need for the drain and the backup?
1.) To start there is a relationship between drain size & flow rate. Flow rate is acheaved by the height of the water line above the drain, combined with the size of the drain. I.e. The more water & the larger the drain, the greater the flow.
2.) How much flow is wanted through the sump/fuge. There are great debates over what is the ideal flow, but a fuge needs a high dwell time for nutrient transfer. So maby, as much as it pains me to use the term, 5xthe size of the fuge for turn over. Flow can be met by powerheads. Simple sumps have no limitations on there flow behyond micro bubbles, heaters, & skimmer performance.
In the over flow thread there I have a link to a flow rate calculater. I'll see if I can add the link here with the blackberry if not will do later.
3.) More than likely it will be either a 3/4" or a 1" drain, pearsonaly I like to use the same size drain for both drains. But here's that relationship coming back. As you move the drain closer to top of the tank, the less flow it can handle. So the backup has to be able to handle grater flow than the primary if & when the the drain clogs (Yes the drain will clog). This helps to set where the drains will be Placed. The distance between, height within the overflow, & so on. The back up needs to be low enough to drain while still not having the overflows water line go above the weir (you knew I'd work it in there some how, fancy word for were the water flows over). While the primary needs to have enough distance between its self & the backup to be fully submerged with out creating a vortex sucking bubbles into the drain (that's what makes noise).
4.) When drilling tanks. There needs to be, at minimum, the diamiter of the hole between the hole & the edge of the panle being drilled. This is the minimum to not crack the glass. More is better.
So figure out how much you want through the sump/fuge. Then put the backup as close to the weir as you can & still achive this flow. Then put the main as low as you can with out cracking the tank. Set water line in overflow with ball valve or gate valve.
What size hole for the return?
1.) This will most likely be the same as the output of the pump. Would expect 1/2" or 3/4".
2.) 3/4" or 1" return plumbing can be split then reduced to 1/2" as it enters the tank.
3.) Without siphion brakes, or other messures to prevent backflow. The tank will drain to these returns when the pump is shut down.
What pump recommendations? (I'll be running an MP40 for the main tank flow)
1.) Normally the least expensive to run. I hate spending money I didn't need to.
I run quiet one pumps for this reason. But to be dead silent eheim is supose to be the best. Untill you steep up to exo's like iwaki (the pretty japaness one) or gen x (the knock off)
2.) Eductor nozzles can reduce the size of pump needed to reach a set flow rate without effecting the drains. (Free flow)
3.) Never reduce the flow to a pump this will cause the pump to cavatate (bubbles).
4.) When picking the pump remember to judge it not only on flow rate but head.
What plumbing parts do I need to pull this whole thing off and where's the best place to get them?
1.) Welcome to the never ending trips to homedepot. Most plumbing will be found at the local box store. Speicalty items like bulkheads will be at the lfs.
2.) Peaces parts
Hose barb fittings (sevral types. 90? Mpt for the main, reg mpt's for most everything else)
A couple feet pvc
Teflon tape (this is your new best friend. Use a lot & once you have tightend the fitting will need to be replased if lossened)
Bulkheads & screens (no open pipes)
90 elbows & other pvc parts
Ball valves/gate valves
Quick conects/true unions
3.) Air leaks cause asperation (bubbles) make sure to have all joints sealed tight
There are pics of my old ten x ten in my tank thread & more info on water in my sig.
Hope this helps. Pm me when there's more questions.
Edited by bitts, 28 June 2010 - 12:38 PM.