Doubling the water volume

[davidstcldfl]

I'm re-working my original system. I'm adding additional grow beds....DWC's.

My system originally held 1000 gals.
Once on-line, the new beds will add an additional 1500 gallons.....for a total of 2500 gals.

The system already has 2 bio-filters, up and running, since the beginning.

My question is......does anyone think, with that much more additional water...will I be starting all over again, as far as 'cycling' goes ?
Or do you think between the 2 bio's and all the bio-film growing elsewhere in the system, that it'll be a non-event ?



Here's the second situation....
As soon as I finish re-working the original system....I'll be starting to build a second system. (separate from the 1st)
When I start up the 2nd system (aprox after a months time)....I was planning on taking one of the bio-filters from system #1. I also was going to take water from the 1st system and add it to the second.

The new system will be 3000 gals.

How much water can I take (at one time) from the 1st system ( to add to the 2nd) without upsetting #1's balance ?

With the 'active' bio-filter being added to the new system and the 'used' water....I'm hoping (dreaming) that my cycling time will be very short....or even a non-event.
Any thoughts, predictions on that ...?

[badflash]

I don't see any issues with your plan. Changing 50% of the water at a shot is OK. When you start the "new" system, move 50% of the water from the old system along with the biofilter. That way not only will you have some nutrients for the plants, you'll have something to feed the biofilter.

[dufflight]

Using one system to seed a second is a fast way to get things going. I'm setting up a smaller system and it will be filled with water from the large system. If it needs water changed it will be from there. I cycled an inside tank this way. You can also add an extra bio filter to let it mature and move this around the different systems depending on fish load.

[jackalope]

I've done the same as above .... even down to almost 25 to 30% .... I didn't have any problems with (re?)-cycling, although I do think that the 50% mark would be a better rule of thumb

[Biggles1212]

Hi, for my 5c worth.

I picture the parts of a system in their function. Adding to your system in terms of water volume, you make it more stable. Making a new separate system makes the whole lot more reliable because any problems in one system will not necessarily affect the other.

If you remove one bio filter from the first system you weaken it and reduce your safety factor for that system.

If your current water chemistry and quality is great, then adding more growing area increase the rate at which you remove nutrients. To keep plant growth quality you will need to compensate with more fish and bio filters. So to keep balance you have to add in like measures everywhere. That might just be a case for a whole new separate system. If you have low ammonia but high nitrates then go for the extra growing areas.

If the water chemistry is good it won't affect you bio filters so when blending it into the new system you just mix very slowly. From my past mistakes with Malachite Green, I've learned the patience of Methusela so I'm extra careful. My fish tank is 5000L with approximately 1:50 ratio of kg Tilapia: 1 Liter Water. I decided to spoil my fruit tress with some water from the tank and then promptly added 300L of water straight from the tap back into the system. The fish look good.

[davidstcldfl]

Thanks for all the input guys...
Duff, I like your idea of building another bio-filter and adding it 'now' to the original system...then moving it later.

Once I get it going...I'll post how it goes.

[dufflight]

I like using ABF(airlift bio filters) you make a new one and just throw it into the fish tank. Then when you start a new system you put it in the new tank. It takes a lot of the spikes out of cycling a new system.

[davidstcldfl]

Hi Duff....Is your ABF, similar to a sponge filter ?

[Brier]

This is a good idea. Tanks don't cycle, filters do. In fact I do a very similar thing inside with aquariums. I keep several extra sponge filters running in established tanks. If another tank needs a filtration boost, I just add a ready cycled sponge filter. Or if I need a hospital tank, I can fill up a 20 gallon tank, drop in a sponge and I am ready to go. I am also interested in the airlift biofilter. I am imagining a huge sponge filter.

[Brier]

Ha found ya! http://www.youtube.com/watch?v=_DJF3pgELXE Really cool! Just like my bioreacter with Kaldnes media, but much simpler! Great design! You could even add a ring around the unit containing filter foam, and it would give you some mechanical filtration. Add some styrofoam to float the unit, and it could compensate for fluctuating water levels. Darn, something new to build!