Fluidized sand bed filter

[+olaggie01]

How do you plan to occasionally clean the sand? Most fludized reactors have a way (at least in pool sand filters) to back flush the system. I don't see anything like this in your design. You mentioned adding some silicon to the top, and hopefully you don't expect to pressurize the reactor as I don't think that the silicone will hold.

[subsea]

I do not think that cleaning the sand is necessary or for that matter desired. You want mature bacteria cultures, do not backflush. Also, with the intense flow in this chamber, no light weight detritus will remain in this chamber. Feed the bacteria.

[+Hydro]

How do you plan to occasionally clean the sand? Most fludized reactors have a way (at least in pool sand filters) to back flush the system. I don't see anything like this in your design. You mentioned adding some silicon to the top, and hopefully you don't expect to pressurize the reactor as I don't think that the silicone will hold.

Like subsea said it it doesn't need cleaning. The rolling sand even keeps the glass clean, at least that's what I read. I do expect silicone to hold the pressure with ease. Silicone holds all our tanks together and there is way more pressure being applied to those joints than what's being applied there. Since its basically free flowing, with the only restriction being the sand, there would only be 1-2 lbs of pressure at most. Plus I use bad*** silicone that glasscages uses for their tanks, dow 732.

[+Hydro]

So the smaller tube made all the difference. I did put a cap on the end of the 1/2" PVC and drilled 8 holes out the side of it, I tried just a straight pipe but it didn't work.

Here is an empty pic, pic with water flow, and pic without water flow.

[Timfish]

It's good to see your floor is a mess but I still say your workbench is too clean. Are you going to seed it with live sand or bacteria when you start it up? I'm curious to see how fast the ammonia drops when you get it running.

[+Hydro]

lol, my floor is messy. I think I spend 1/3 of my time working, 1/3 looking for tools, and 1/3 cleaning up the messes I make!

I've been wondering if I needed to seed it or not, I'm hooking it up to the system that has had a tank running a couple of weeks now with a couple shrimp and fish in it. I was going to add some LR to the system probably tomorrow. Do you guys think I need to seed it with store bought bacteria?

[victoly]

I don't see any reason to seed it. Since it is essentially barren, it should colonize as if you were adding dry rock to a tank. Very cool and exciting!

[Timfish]

I'm undecided but whichever you do can you test ammonia frequently?

[+Hydro]

I think that I will pick up some bacteria this weekend, can't hurt. Yes I will keep a close eye on ammonia, I'll post here how well it is working.

[subsea]

With this technique do you use a protein skimmer?

By favoring arobic bacteria, you will have much nitrate as a by-product. Get the underwater light cranked up, you will need algae to uptake nitrate that was converted from aerobic bacteria. Instead of DSB methods which have nitrifying bacteria and de-nitrifying bacteria going on, you will have skewed the bacteria job into aerobic only which means more nitrate to process. Often when macros are required to pull nitrates, they self limit because of low iron. You may consider iron concentrations to supply macros with all of the nutriants to grow rapidly. In my lagoon tank, I am putting in some frresh water planted media that is high in iron, for the reason that I just mentioned.

Patrick

[wesreyn]

I think that I will pick up some bacteria this weekend, can't hurt.

+1

[+Hydro]

With this technique do you use a protein skimmer?

By favoring arobic bacteria, you will have much nitrate as a by-product. Get the underwater light cranked up, you will need algae to uptake nitrate that was converted from aerobic bacteria. Instead of DSB methods which have nitrifying bacteria and de-nitrifying bacteria going on, you will have skewed the bacteria job into aerobic only which means more nitrate to process. Often when macros are required to pull nitrates, they self limit because of low iron. You may consider iron concentrations to supply macros with all of the nutriants to grow rapidly. In my lagoon tank, I am putting in some frresh water planted media that is high in iron, for the reason that I just mentioned.

Patrick

I will still be using an undersized skimmer (all I got at the moment) with the system. The sand filters are said to strip the water of oxygen so I thnk that I at least need the skimmer to help oxygenate the water.

Thanks for mentioning the iron, like you said I need to supply everything the macro needs to grow fast, not just nitrate and light. What is the safest way of adding iron? Should I just add some of the media you are using to my fuge? Can you test for it?

[+Hydro]

In case anyone is considering this there are a couple of things to warn about. If the power goes out the sand bed filter can start to die off in less than an hour. I'm considering buying an air pump and one of those plug in battery pack that will turn on when the power goes out.

Also like I mentioned above the filter strips oxygen from the water and can lower the ph because of this. I will be making adjustments if this is a problem, I may add a huge air pump in the sump if necessary.

[offroadodge]

wow, wish i were/had the time to study these things. I would love to add an outside macro tank fro nutriant export or something. Love all the ideas Hydro!!!

[+Hydro]

Thanks Jermey

Funny story, I siliconed the top on the filter and hooked it up and the bulkheads leaked....I forgot to tighten the bulkheads first....doh! Had to cut the top back off, tighten them, and silicone back on.

Well I barely got the sand filter going before I left for california. I really wanted it running while I was gone to get it seeded and useful asap. I went ahead and bought the bacteria and had it added every day now for almost a week. I learned a couple things about this that I can pass on.

The filter needs to be left running drain to waste for at least 24 hrs before hooking up to the tank system. The filter released lots of fine sand in to the system which was tough to filter out and its stuck to everything. I did run it drain to waste off a water hose for a couple of hours but that wasn't enough. I'm sure that the sand rubbing together broke some of it down making more dust after I did this.

It was also very hard to get started especially since it is 5' off the ground. The sand was packed down around the outlet inside the filter and it was hard for the pump to push it out. I had to use compressed air on the supply line to blow the sand from around the outlet. Once I did this the water flowed very slowly even with the pump turned on high. I was bummed out watching it fill up at a trickle thinking it wouldn't work. I thought maybe once it filled up and water started to drain back the suction might kick it off. Once it was filled it didn't make any difference......until I leaned it over and got the air bubble out of the top.....then WHOOSH!!! The water shot out of it so fast I thought it blew off one of the lines. After I got started I was able to turn the pump to low and actually had to close the valve some because it was flowing to much and pushing the sand to high. Now that there arent any air bubbles in the filter restarting it isn't an issue.

I had biocubed check the amonia while I was gone and it was around .25, not sure if my test kit is accurate though. Nitrates were around 10 ppm. We will see how the filter does for this over the next week or two.

[+Hydro]

You mentioned adding some silicon to the top, and hopefully you don't expect to pressurize the reactor as I don't think that the silicone will hold.

Just to be sure I I wouldn't have any leaks I hooked it up to city water and turned the flow on all the way, no problem at all. I even put my thumb over the return line to create even more pressure and it help just fine. This was about 10x more water pressure than it is operating at now.