About to setup my 120gal fish tank and was wondering which bulkhead is the drain and return. I have one that's larger than the other. Also I'm running a danner mag 1800 gph return pump. What size pvc should I use for drain and return. Thx for any help.
Help with pvc and bulkheads
- Thread starter j-lor
- Start date
The larger one is for the drain. What size are the bulkheads... cause you can't go larger it won't change the math. But in my 180g I have 2x 1" bulkheads for drain and wish they were 2". And had more than 2 drains.
Also what you planning to stock and how many plays apart in the water flow
Also what you planning to stock and how many plays apart in the water flow
Just a FYI, I always use drill holes for drains, and never returns. I always use PVC lines placed above the tank for returns. The smaller drain (sometimes used fo redundancy) just might save you from a tank overflow, if used as an extra drain.
And since you haven't yet stated the size of the bulkheads, any pipe smaller than 1.5" is very easily plugged. Anything from plants, to snails, to a dead fish can block a small drain line enough to create a tank overflow.
An example, the photo below is a 1.5" drain plugged by water plants when cichlids started uprooting plants for spawning.
I also use return lines above the surface to create agitation, which help promote aeration and gas exchange.
And since you haven't yet stated the size of the bulkheads, any pipe smaller than 1.5" is very easily plugged. Anything from plants, to snails, to a dead fish can block a small drain line enough to create a tank overflow.
An example, the photo below is a 1.5" drain plugged by water plants when cichlids started uprooting plants for spawning.
I also use return lines above the surface to create agitation, which help promote aeration and gas exchange.
Although bigger is sometimes better in terms of stand pipes, I dont know if anything smaller than 1.5" is prone to clog. It directly also depends how the pipes are being implemented. If you are using with internal or external overflow boxes having weirs that reduces significantly of any clogs. Also, if you use Bean Animal or Herbie you should use a strainer on the full siphon pipe which prevents anything big from clogging. Even if you have stand alone with no overflow box, strainers will help.
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Given that you have a return pump, I assume you have a sump? You could also T off the PVC connected the the pump outlet to have dual returns going back to the tank. Gives some flexibility for water / surface agitation. I like using loclines for the returns.
How are your two 1" drains being used? Are they standing in your tank with no overflow box". Do you have then a gate or ball valve reducing the flow to create the siphon?
Dont mean to go on tangent but addressing this may also help OP?
OK. Are you sure the drains are the bottleneck and not the weir/teethe. How far below the water surface is the full siphon drain? If the 1" drain are down low enough I find it should have no problem even closed off a bit with gate valve. Dont want to pursue if you're not interested in possibly tuning, but some adjustments may help .