Can someone look over my design and make sure my plan isn't fucking retarded?
I was going to get 4 20 gallons and hook them all together side by side using fish bridges like in the picture. Then to get decent flow I was going to get a canister filter and attach the intake in the leftmost tank and the output in the far right. The water should just flow in a big loop and be fine, right?
Also I was hooking up a DIY chiller to it. Would something like this need an additional pump because of the tubing length, or no?
the main drawback to your setup that I can see is that evaporation loss will lower the water level and if it goes low enough you'll lose siphon on the bridges and the filter will pump the contents of the last tank onto the floor. This will particularly be a problem if you go on vacation or ignore the tanks for a week or two.
In marine tanks with sumps we get around this problem by using a peristaltic dosing pump to add topoff water. Often the topoff pump will be run by a float switch.
Thanks, I'll post pictures if it works. My goal is to have a different species of newt in each tank, and to put screening over the opening to the bridge so fish can get through but the newts can't.
Yeah, I'd have to definitely be careful about evaporation, but figure it shouldn't be too big of an issue if I put the openings to the bridges like 6 inches underwater. Sumps always scared me, but since everything here should be under a vacuum I don't think i'd have to worry about an outage or anything as long as I kept an eye on evaporation.
Also if anyone has suggestions for small inexpensive fish that will do well at mid to low sixties i'd love suggestions. My plan right now is just some white clouds, fatheads, and maybe a few hillstream loaches if my flow and algae growth end up being enough.
>it shouldn't be too big of an issue if I put the openings to the bridges like 6 inches underwater
The thing is all the evaporation from all 4 tanks is going to gather in one tank. If I'm thinking right it'll be your last tank because that's where water is being pulled from.
So the water level in the first 3 tanks will always be full, but the last tank will lose water to evaporation 4 TIMES AS FAST.
this means you could conceivably lose six inches in water level in less than a week depending on conditions in the house.
Using cold water will make this less of a problem, but it could still be a problem.
Wait..what? Wouldn't that not matter because if my physics are right the bridges wouldn't let the individual tanks have different water levels?
Why would it only evaporate in the last tank?
Even so it shouldn't be a big deal because I'm doing water changes on various things all the time so topping off is just a matter of swinging the python a few feet over while I'm filling something else.
I was debating on doing this all as one big tank with dividers but figured the bridges would be neater and also save me from having to worry about limbs getting bitten off through the divider.
You're both pushing and pulling the water through the system, but where the siphon matters is in pulling...
Water only flows through the system if the water is HIGHER at the start and LOWER at the end... water in a siphon moves downhill.
So the first three tanks in the circuit will always have the same water level, completely full. Because the first tank is completely full. Fed by the pump return.
the last tank doesn't need to stay completely full, there's no siphon from it to the next tank. The water is leaving it by pump, not siphon. So the pump will effectively lower the water level on the last tank to keep the first three full....
the result is that the evaporation from all four tanks is going to only lower the water level on the last tank. The first three are kept constantly full by the pump, and the pump will keep the last one from filling.
Not OP but are you sure?
The water would be pulled into the last tank, from the second to last, third, fourth. So as long as the water is pulled from the other tanks from the tubes due to vascular pull the water level in all tanks should remain the same even after evaporation.
that would only work if the tanks are all hermetically sealed.
then vacuum would lower the water level on the first tank only.
but since they aren't sealed it's not working as a vacuum. It's working as an overflow, which means the water level on the first three tanks must be higher than the last to have flow.
If he shuts the pump off all four would settle to the same level, but as soon as the pump turns on water will lower in the 4th and rise in the first 3.
the water level will always be lower than the other 3 as long as the pump is running, so putting the tank higher will lower the water level. If you set the bottom of the last tank higher than the tops of the first three, the pump will suck air and the circuit won't flow.
however you set the height of the tanks though, the ends of the siphon tubes have to always be below the waterline of each tank whether the pump is on or off. Otherwise you get a flood.
yeah, he said he's putting them 6 inches down which should be plenty, especially on a cold water system that shouldn't evaporate much.
If it was me I'd probably run the last pipe end almost to the bottom of tank 4, just to be safe.
Yeah, thats a good idea, I think i'll do that just to be safe!
My other big question was about needing a pump or not. Should I add a pump to the tubing that attaches to the canister filter? I'm not convinced my canister would be strong enough to push water through the 100 feet of tubing in the fridge and then also pump it through all the bridges. Or would the physics of the whole system being a giant loop make it work out?
length of tubing only matters for calculating restriction and friction.
head height is what actually matters. How high it needs to pump is more important than how far. If your pump isn't up to the task, try raising the canister up slightly above water line.
>try raising the canister up slightly above water line.
actually that's probably a bad idea. when you shut the pump off any part of the chiller circuit above the waterline will drain into the display tanks.
Even with the water line would be best.
No I mean I thought you -couldn't- have a canister above the water line. Every canister filter I've seen was gravity fed and then used a pump to push the water back up into the tank. Instructions always said they wouldn't work unless they were below the water line.
they lose prime if they're well above water line and you stop them. a one-way valve on the inlet line prevents that though. So you can run it above the water line if you need to.
right at the water line would be better though. Save you the trouble of plumbing a backflow valve.
you're wrong. because they're filters and not just pumps they can lose prime while running and a one way valve is not enough to prevent it. Most canisters HAVE to be below water level