Looking for DIY Wet/Dry Trickle Filter

I know ther's allot of DIY when it comes to SW tanks, but are there DIY's for FW system? I would like to build a wet/dry trickle filter for my 75g cichlid tank. I have no idea where to start on a build like this, so if anyone can post links or where to look at a build like this, it would be very useful to me.
 

carmexx

Active Member
I used a 20 gallon tank and built a rack system out of 1/2" pvc to accomodate 4 trays of bio balls and ceramic rings. They sit on egg crate in layers and the top layer is where i put my media bag....bio-chem zorb or chemi pure. The only drawback to my build is water noise. The overflow hose dumps directly into the top media tray and u can hear splashing. But I tolerate it.
 

DaveK

Well-Known Member
I built several of these for SW systems. While I no longer recommend them for that application, they are excellent for the cichlid tank you plan.

First, do not over do the bioballs. You want enough to be a biological filter, but no more than that. Usually you want about 1 gal of bioballs per 10 gal of water. So for a 70 gal tank you want about 7 gal of bioballs.

Second, you want to keep the bioballs from being submerged in water. If this occurs, the biological activity on the submerged balls is far less, and they also become a major oxygen consumer.

Notes - Not in any special order.

It's not necessary to install the trickle filter below the main tank. You could install it above the tank and pump water up to it. If you do it this way, you don't need an overflow.

You should prefilter the water going to a trickle filter. Any type of decent mechanical filtration will do.

I built a very nice trickle filter out of a 20 gal extra high. (It has the same base of a 10 gal tank but it's twice as high) I installed a baffle dividing the tank vertically into about 2/3 and 1/3. The baffle only ran to about 5 inches from the bottom of the tank. Where the baffle ended I installed a section of egg crate to form a base for the bio balls. Then I built a drip tray that almost filled the bio ball area.

Tricks to building a drip tray. I used 1/8" thick acrylic plastic. The base plate can rest on top of the bioballs. The sides only need to be about 1" high. 1/8" holes spaced 1" apart on the base plate work well, but keep the holes about 1 1/2 to 2 inches away from the sides of the drip tray. I also found that it helped if you use a 3/8" drill and just touch it to every 18" hole on the bottom of the drip plate, sort of as if you were drilling to counter sink a screw.

Plumbing to the drip tray. You want to use a T or several to disperse the water across the surface of the drip tray. This give much more even flow to the trickle filter.

You can drill a hole in the side of the tank and install a bulkhead fitting, if you are using an external pump or if you want to mount the trickle filter above the display tank, and let gravity do the work. Otherwise, you can just use a submersible pump in the trickle filter.

Lastly, you have a lot of latitude in the design of a trickle filter. It's not nearly as critical as the design of a skimmer or overflow is. So if things are a little off or just different, there is no problem.
 

DaveK

Well-Known Member
I thought this looked interesting. And simple :)

Well, the price is right, but I'm not impressed by the design.

For a trickle filter to work it's best it's got to have some air flow through the bio media. In addition, the use of plastic scrubbers will cause the water to channel, since they are not uniform in the air to media ratio. There are also gaps in the bio media. There is also a problem with the way the drip tray is drilled, since it will lead to non uniform flow through the bio-media.

This would be a lot better design if the hole spacing in the drip tray was more uniform, and if the bio-media was more conventional, and the airflow through the trickle filter was better.

Even so, it will still work, it just will not work as well as it could.
 
I built several of these for SW systems. While I no longer recommend them for that application, they are excellent for the cichlid tank you plan.

First, do not over do the bioballs. You want enough to be a biological filter, but no more than that. Usually you want about 1 gal of bioballs per 10 gal of water. So for a 70 gal tank you want about 7 gal of bioballs.

Second, you want to keep the bioballs from being submerged in water. If this occurs, the biological activity on the submerged balls is far less, and they also become a major oxygen consumer.

Notes - Not in any special order.

It's not necessary to install the trickle filter below the main tank. You could install it above the tank and pump water up to it. If you do it this way, you don't need an overflow.

You should prefilter the water going to a trickle filter. Any type of decent mechanical filtration will do.

I built a very nice trickle filter out of a 20 gal extra high. (It has the same base of a 10 gal tank but it's twice as high) I installed a baffle dividing the tank vertically into about 2/3 and 1/3. The baffle only ran to about 5 inches from the bottom of the tank. Where the baffle ended I installed a section of egg crate to form a base for the bio balls. Then I built a drip tray that almost filled the bio ball area.

Tricks to building a drip tray. I used 1/8" thick acrylic plastic. The base plate can rest on top of the bioballs. The sides only need to be about 1" high. 1/8" holes spaced 1" apart on the base plate work well, but keep the holes about 1 1/2 to 2 inches away from the sides of the drip tray. I also found that it helped if you use a 3/8" drill and just touch it to every 18" hole on the bottom of the drip plate, sort of as if you were drilling to counter sink a screw.

Plumbing to the drip tray. You want to use a T or several to disperse the water across the surface of the drip tray. This give much more even flow to the trickle filter.

You can drill a hole in the side of the tank and install a bulkhead fitting, if you are using an external pump or if you want to mount the trickle filter above the display tank, and let gravity do the work. Otherwise, you can just use a submersible pump in the trickle filter.

Lastly, you have a lot of latitude in the design of a trickle filter. It's not nearly as critical as the design of a skimmer or overflow is. So if things are a little off or just different, there is no problem.

I understand what your saying Dave, but I need to see drawings or pictures to help me understand the general layout. My sump that I'll be keeping for my future reef build, I watch videos of constructing a sump with the baffles and looking at different pictures/diagrams of sumps that others had done. To help me actually build my sump with a few modifcation due how much water I want to be in the fuge section, which is more than the water line of the first 2 section.

Also what size tank be good size for a 75g tank, since my DIY Stand can accomodate up to a 55g.

I thought this looked interesting. And simple :)

Pretty sure it works for him, but myself I want to use a used tank and turn it into a wet/dry.


I was wondering by building wet/dry, would it be possible to use a canister filter to be use as the mechanical/chemical filter and the wet dry for the biological, by running the output of the cannister to the wet/dry to feed it and pump the water back up with a water pump? Is this good or bad idea and they should be kept seperate?
 

DaveK

Well-Known Member
I understand what your saying Dave, but I need to see drawings or pictures to help me understand the general layout...

I was wondering by building wet/dry, would it be possible to use a canister filter to be use as the mechanical/chemical filter and the wet dry for the biological, by running the output of the cannister to the wet/dry to feed it and pump the water back up with a water pump? Is this good or bad idea and they should be kept seperate?

This was a DIY project that I did many years ago and no longer have, so I don't have any pictures. I'm also away on vacation, and this small laptop doesn't have a decent program to draw you a diagram. So... give me 4 or 5 days to get home, and draw up something for you. If you don't see anything in in that time period, PM me on RS and remind me.

Ideally, you want to run a filtration system in the order of mechanical, biological and chemical. The idea being that you want to remove large particulate matter before the biological filtration needs to deal with it, and you want the biological filtration to deal with waste products before the chemical filtration, to preserve the chemical media.

That being said, it's really not all that critical. However, I don't think it would be a good idea to use a canister filter to feed a wet dry. First you'll expend the chemical media faster, and second unless the canister head is below the water level in the sump, you risk it running dry if you have a power failure, and the canister back siphons.

IMHO, this is more trouble than it's worth. It's far easier to plumb off the main return pump, routing water to any carbon or phosphate reactor or anything else,
 
K dave you say 1 gallon of bioballs per 10 gallons. for a 75 I need 7.5 gallons of bioballs. I'm kewl with that.

Now with a wet/dry, I can do away with the canister right? If so then I have a tank I can use to turn into a wet/dry, that would be my 55 sump. I'll Have to figure out how to remove the walls since the glass pieces are a close fit. I might be able use a fishing line and draw it from the top to the bottom to cut the silicone that is sandwich between the walls and the tank itself.

After seeing some vids on wet/dry I got a design rolling around in my head, i just need to draw it. I would still be interested in your drawing of the wet/dry Dave.
 

DaveK

Well-Known Member
You can see that you don't need too much room for a wet/dry filter. If you picture a 10 gal tank you can see 7.5 gal of bio balls would fit into that with lots of room to spare.

One other thing I didn't mention, to a point, you are better off with a tall tower of bio balls, compared to a wide one. In other words a tower 12 inches square at the base and 24 inches tall is better that a tower 12 by 24 inches at the base and only 12 inches tall. The higher tower gives better gas exchange.
 
I understand about the tower of bioballs. back to the blueprint board to redesign the wet/dry. Geesh this is so much fun. :lol: You gotta love DIY's

th square base does it matter the size, say beside like 12 could a 10 work? Also at the top of the tower from the trickle plate to the top of the bioballs how much space would be sufficient and how much space would be to much. I like to design this wet /dry where it wouldn't be to noisy. Could always modify the stand, the section where the wet/dry set in and use some kind of sound dampening on the inside of the stand.

I'm thinking like a 10 or 20 should be big enough, but of course it means i have to look around for a use one or buy new, but I do have a 29 that I need to finish stripping the silicone out and put fresh in.
 
doing some calculation on the bioball tower. using the following dimension will give me 7.79g 12 x 12 x 12.5 so would the 0.29 be enough space between the bioballs and the trickle plate, if not then I can do 12 x 12 x 13 and it gives me like 8.1g.

------- SCRATCH ABOVE -------

29g isn't 12 wide it's actually 11 3/4 wide so I did new size.

11 3/4 x 12 x 13 would give me 7.94g if I increase the 13 1/4 to 13 1/4 then it would give me 8.09g.

I'm thinking the 7.94g would be good since I'm only going to be using 7.5g for bioballs and it would leave 0.44g of air space. but for a better gas exchange would i need a bigger air gap between the top of the bioballs to the trickle plate.

As you can tell I never dealt with a wet/dry for FW, because I always used canister's in the past always wanted to go to wet/dry even back then.

also in the water return section could i put like the heater in there like you would for a sump for a SW system, to where I don't need it in the DT. Also one area I haven't touch yet on this setup, and that is the overflow.

I know I won't need a big overflow like 1500 gph, what would be good flow rate for the overflow to drive the wet/dry.
 

DaveK

Well-Known Member
You can set the drip tray right on top of the bioballs. Some people will also inject air into the base of the bioballs using a small air pump, You do want some sort of gap so air can circulate in the bioball area.

Canister verses trickle filters. Depending upon the type of tank being kept, determines the filtration system. Because the gas exchange is so good in a trickle filter, just about all the CO2 is removed. For a cichlid tank, where you have no live plants, this is exactly what you want. If you were doing a planted tank, you want the CO2 to encourage plant growth, so a canister filter is a better choice.

Ideally you want to use internal overflows, even if you need to drill the tank. They cause a lot less problems. If you can't do that, then get a Lifereef overflow. They do cost more than the others that use a long U siphon, but Lifereef overflows are not prone to failure.

You could build an overflow, but over flow design is more complex than that of a sump. Expect a few floods and expect to rebuild a overflow a few times to get it right.

Yes, you can place a heater in the sump.

I'd want a turn over rate of about 3 to 5 times an hour. Remember contact time with the bioballs is important, and you don't want to over do the flow. If you need more flow in the tank you can always add a powerhead or two.
 
k. as far as the turn over I want to shoot for 5x, so with this tank i'm looking at about 375gph. I know glass-holes.com has an overflow that is rated 700. So I'm thinking that would be good choice to go with.

I'm thinking also instead of using a tank to build, just build the wet/dry from the ground up. Need to know which could be cheaper glass or acrylic to build a wet/dry and how thick would the piece needs to be. I know 1/8" would be to flimsy so would a 1/4" for glass or 0.25mm for acrylic be the thickness I should go with.

As far as powerheads goes. planning on adding 1 or 2 small ones to give a small current in my cichlid tank to help move wate little around the rocks and thru the rock formation, after all this will be a African Rift Lake (Malawi Mbuna) tank.

I'm putting in plenty of planning and research for this particuliar tank. The Back Glass planning on painting it Black and I might do the same for the side glass not sure yet, because my stand I might build the side up to make the stand to look more like a cabinet type of look.
 

DaveK

Well-Known Member
If your going to build a trickle filter from the ground up, consider using something like a 20 long for the sump, and just building the bioball tower. Using a tank as the base will be lots less expensive than getting glass or acrylic and building it yourself.

There is almost no weight to the bioball tower, so you can build it out of 1/8" acrylic.

On painting the back glass. I would recommend using a dark color, but not black. Use a very dark blue, or brown, or green or a combo of all. Black by itself is a very dull uninteresting color. For example, look at most of the great art. While the painting may be dark, a pure black is seldom used. There are artistic reasons for this,
 

Rhodes19

Active Member
Bobby, whats the update on your wet dry? I am starting to look at making one for my 45 g with my wife's 5 blood parrot cichlids in it. Any pictures? Thanks.

Chris
 
Hey Rhodes, nothing on that front yet. I do have a 55 that is cycling right now. in my signature the link to Sinister FW 55 gal build. is to that build. Still haven't decided on that tank yet except for the aquascape I want to do on that tank.

I need to get a camera to get pics. My brother wife needed her camera back about 6 months ago.

My 75 I was gonna turn it into a cichlid tank, but the plans for it had changed once again. lol Now it will be a Fowlr then eventually turned into a reef tank.

Back to the 55 it might take me a little time to aquascape it the way I want it. Monthly bills are digging in the pocket book a little deep. The 75 FOWLR I'm hoping to start working on it this winter, to get what I need for it, since I already got the 55 gallon tank that been turned into a sump and a protein skimmer.
 

Rhodes19

Active Member
Hey Rhodes, nothing on that front yet. I do have a 55 that is cycling right now. in my signature the link to Sinister FW 55 gal build. is to that build. Still haven't decided on that tank yet except for the aquascape I want to do on that tank.

I need to get a camera to get pics. My brother wife needed her camera back about 6 months ago.

My 75 I was gonna turn it into a cichlid tank, but the plans for it had changed once again. lol Now it will be a Fowlr then eventually turned into a reef tank.

Back to the 55 it might take me a little time to aquascape it the way I want it. Monthly bills are digging in the pocket book a little deep. The 75 FOWLR I'm hoping to start working on it this winter, to get what I need for it, since I already got the 55 gallon tank that been turned into a sump and a protein skimmer.

Nice set up. You'll have to get a camera and post some pics. Yeah, aquascaping for me takes while. I'm always changing it to make it look better. Its a work in progress!! LOL
 
yeah i think thats the fun part, is create a aquascape, then within a week you come up with a better way of doing it. I'm hoping to geta camera over the next couple of months, So that way I can get pictures. It really sucks not having a camera.
 

bbe22

Member
So, what kind of cichlids? African or South American? I'm with Dave on the numbers. I've built two wet/dry's. I can say that I really recommend elevating a wet dry and letting it pour into a sump. That may seem obvious, but I have acrylic store varieties now, and I found out the hard way that having that sump makes all the difference in the world. If the power goes out, or your me and turn the pump off and walk away not realizing your tank is overflowing out of the wet/dry, it has a place to go. My wet/dry on the fw tank sits in a 35 gallon rubbermaid tub. Never had any problems with that tank, and I plan on adding a sump in the sw tank after my lessons in cleaning saltwater off the floor by the gallon.

I work in the food and beverage industry, and my solution to the trickle plate came in the solution of green pot scrubbers. They are for scrubbing teflon pans and plates without scratching them. They are about 1/8"x2"x4". What I did was stacked them up like a pyramid to help disperse the water over the drip plate. Works like a charm, and they've been in there over a year and are as good as the day I put them in, never cleaned them once either. So if you know anybody that works in a restaurant try to get them to hook you up. One lesson I did learn was that in sumps, water doesn't always get the proper flow. I added a powerhead to mine to get rid of the stagnant pockets.

If you end up taking the canister off, don't do it for at least a couple of weeks, for the bacteria. I figure you know this, but just wanted to mention it. I use my old school E-heim as a powered buffer; I stuffed it with peat moss and run my co2 into the intake. The whole thing sits in the sump, and the intake and out-take are both in in the sump, as it isn't really strong enough to push water into the top tank. What's your plan for an overflow and a pump?


Hope this helped, sounds like you've got a plan. Take pics during the build!
 
Top