wet dry filter --???

[heavyhitter]

Hot water in a closed system is way different than an open system with algae buildup etc...they don't really clog but they could foul if you don't keep them clean ...

I think Zennzzo nailed it.

IMO back siphoning will ONLY occure from a poorly thought out sump system. This may or may not be a probem for your setup. Need more info on your setup to know if you may or may not have to worry about it. (depth of the output hose, volume of your sump)

 

[Jgray152]

IMO back siphoning will ONLY occure from a poorly thought out sump system. This may or may not be a probem for your setup. Need more info on your setup to know if you may or may not have to worry about it. (depth of the output hose, volume of your sump)

back siphoning will occur in any sump system which has the output or intake below the water line.

I wouldn't trust check valves. Pick out a sump that will hold the water which will be siphoned from the aquarium. Usually its .5"-2" water level drop.

Length * Width * Water Level Drop in Inches = Cu/in * .0043 = Gallons Siphoned.

 

[NOLAGT]

You can use this calculator

dont use check valves...just drill a small hole for the siphon brake. i think check valves can clog and also reduce flow....

http://www.reefcentral.com/calc/sump.php

 

[Jgray152]

No, don't use that calculator. Its not safe at all.

Reason one. If you enter the dimensions 48" length, 24" wide, 2" above overflow, it will tell you that a 10 gallon sump will be fine.

48x24x2 = 9.9 gallons. This leaves no room for the continuous water level in the sump while its running, which is usually 6" or more. It also does not allow for media.

It also does not take into consideration the total aquarium gallons. Example, my dimensions 48x24 could be 48x24x48 equals 237 gallons. A 10 gallon sump will not handle a 237 gallon aquarium. It won't even handle the siphoned volume when there is water already in the sump and the plumbing.

If you wan't to use a calculator that takes lots into consideration,you can test out mine which is still in development. Look in the DIY section for a thread called "Aquarium Sump Calculator".

The only thing that calculator is good for is figuring out the volume of water siphoned from the aquarium and can not calculate for the total sump tank volume.

 

[NOLAGT]

That calc tells you how much water your sump needs to handle if power goes out...not how big your sump should be. So if you take a water level measurement like 48"x24" at 2" over the over flow it doesnt matter if your tank is 48" tall like your 237 example as far as how much water will end up in the sump if power goes out. So you have to fig ok I need to have at least 10gal of EXTRA room in the sump for water when power goes. Its up to you to know your sump is say a 30gal tank....take out your constant water levle and media ( lxwxh in inches devided by 231) and see what you have left...is it at least 10gal. You can also add in your GPH and it tells you a recomended sump size as well...but its just a recomendation.

I didnt look at your calc in the DIY section...

 

[Jgray152]

The Title "Sump Volume Calculator" is deseiving. It should be something along the line, Aquarium Siphon Volume Calculator or something of the sort. Many get confused with this calc.

So if you take a water level measurement like 48"x24" at 2" over the over flow it doesnt matter if your tank is 48" tall like your 237 example as far as how much water will end up in the sump if power goes out

Correct. It was just an example.

The reason I jumped so quick to say "no don't use it" is because I made a thread on cichlid-forum.com about my calc in progress and some mentioned this exact calc to determin the correct sump tank size which it can not do safely. Using the flow rate variable is not the only variable it should take into consideration.

 

[NOLAGT]

True...and no worries about jumping so quick on it. I use it simply to see what it has for what kind of water in a round about way do I need to fig for when im sizing my sumps. It could have been me on C-F that posted it lol. Its the one I have always used...not complete but useful to me.

For instance for my 240 long and running my target of 2000gph into the tank it has me needing 20 gal of extra room for water if the power goes out and a MIN. sump of 40 gallons. So its not that far off in that instance....im going to use a 55gal tank...a tad taller than a 40gal long tank.

 

[heavyhitter]

back siphoning will occur in any sump system which has the output or intake below the water line.

Yes I should have worded it differently. I phased that poorly.

IMO back siphoning will ONLY over fill your sump from a poorly thought out sump system.

 

[NOLAGT]

IMO back siphoning will ONLY over fill your sump from a poorly thought out sump system.

True that...and you will find out very quickly once you kill the power

 

[Jgray152]

Well. The flow rate has nothing to do with how much water is going to be siphoned out of the aquarium when the pump shuts down.

You also need to consider the volume of water in the piping. For 2000 GPH, I think you need 2" pipe. If you have 10' of 2" pipe, you will have roughly an extra 1.62 gallons of water in the piping its self. 15' is equal to about 2.43 gallons. This is another variable you need to consider on top of the siphon volume from the aquarium.

I would like to know how it justifies the size sump according to the flow rate.

It can help, but surely not to be soley dependent on.

a MIN. sump of 40 gallons.

There are two standard 40 gallon sump sizes.

Just for an example. A 20 gal sump, is not just a 20 gal sump. There is a big misconception with this. What you really need to do is look at its dimensions ad the "actual" holding volume. Not the rounded off number from the manufacture.

20 Gal Long: 30x12x12 = 18.2
20 Gal Tall: 24x12x16 = 19.4

40 Gal Long :48x12x16 = 38.9 Gallons
40 Gal: 36x18x16 = 43.9 Gallons

When you figure the water level in the sump that it will be when its running, say this is 8" high.

20 Gal Long: 30*12*8 = 12.38 Gallons
20 Gal Tall: 24*12*8 = 9.91 Gallons

40 Gal Long: 48*12*8 = 19.81 Gallons
40 Gal: 36*18*8 = 22.29 Gallons

When you pick out a tank such as a 55 gallon, there is really only one standard size so you don't have much to worry about.

55 Gal. 48x13x20 = 52.7 Gallons.

Now for a real example.

240 Gallon aquarium. 96x24x24 = 237.77 Gallons (not factoring for glass thickness)

1" water level drop in the aquarium would be = 9.91 Gallons
2" x 10' piping = 1.62 Gallons
8" Sump water level when running in a 55 gallon = 21.47 Gallons

All of which adds up to 32.99 Gallons. You have an extra 19.7 Gallons of room which will be lessend when adding lots of bio media.