UV and cycle

gordob

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Should I wait until my cycle is complete before I start running my UV sterilizer? (It's been a while since I cycled a tank!)

Thanks,
Brad
 
yeah, I agree... (I would suggest cycling at least a week longer than anyone else recommends.. )

longer cycle will help you to create a more stable system in the long term.. (assuming you dont do things in the future to jeopardize it)


you don't have to run your lights, skimmer, UV... any of it.. while you're cycling..

(I guess Lights are ok, but if you do, you're just going to have more green hair algae to get rid of..)
 
Lights have actually been shown to inhibit nitrifying bacteria.

Stable pH and alkalinity are very important.

A high dissolved oxygen level, greater than 80% saturation, is desireable.

A source of inorganic nitrogen, usually ammonia, is required for nitrifying bacteria. The ideal level should be around 4 ppm. Higher or lower than that is less desireable.
 
I would leave it on from the beginning. Most of your bacteria is attached to the substrate, not free floating. If leaving it on during cycling had any ill effects the n would it not manifest those same effects after cycling?
 
grouper therapy;626549 wrote: I would leave it on from the beginning. Most of your bacteria is attached to the substrate, not free floating. If leaving it on during cycling had any ill effects the n would it not manifest those same effects after cycling?

During tank cycling virtually any surface may become colonized with bacteria including the substrate, walls, rocks/pores, filter media, plumbing etc. The nitrifying bacteria we are interested in have been shown to be sensitive to short wavelength light from the blue into the UV (from around 470 nM and shorter). These are wavelengths of highest prevalence in most properly lit reef tanks.

These bacteria are spread by means including dispersion via the water column. During that time, light may inhibit and/or kill them. Once the tank is cycled, the bacteria on surfaces exposed to light may not be suitable, but at that point it will not matter. Light only serves to slow down the cycling process, and perhaps promote algal growth.

See below references for more information.

search
 
I agree that the light will destroy the bacteria IF it passes through the uv, that does not necessarily slow the cycling process if enough bacteria is established on the substrate which is more likely to be the case. More bacteria is not an absolute for the cycling just the presence of the bacteria. I've set up systems with and without uvs and have never experienced any delay in cycling while running an uv.

Edit: Longer cycling does not necessarily create a more stable environment either. While it is necessary to wait a sufficient time to colonize bacteria ,the main thing to help stabilize the system is to add the bioload at a reasonable rate allowing the bacteria to colonize at the same rate. What that rate is I'm not sure but I would think one should err on the slow side. I've seen too often., the tank completes it's cycle one fish is added and does fine, a few days later 2 more are added then next week 3 more are added. All of the sudden the fish are all stressing and dieing creating an ammonia spike and either stressing or killing half if not most of the fish.
 
grouper therapy;626580 wrote: I agree that the light will destroy the bacteria IF it passes through the uv, that does not necessarily slow the cycling process if enough bacteria is established on the substrate which is more likely to be the case. More bacteria is not an absolute for the cycling just the presence of the bacteria. I've set up systems with and without uvs and have never experienced any delay in cycling while running an uv.

Edit: Longer cycling does not necessarily create a more stable environment either. While it is necessary to wait a sufficient time to colonize bacteria ,the main thing to help stabilize the system is to add the bioload and a reasonable rate to allow the bacteria to colonize at the same rate. what that rate is I'm not sure but I would think one should err on the slow side.

I was referring to wavelength's from lighting, not a UV filter. The light from a Metal Halide for example, can inhibit or destroy nitrifying bacteria as well, per the references.

As to rate of colonization, I have used bacteria cultures and cycled in ~5 days using ammonia at ~4ppm, as well as the long (4-6 week) method with fish. Both work, I just prefer using the bacteria. Both are preferable to do without light of any kind, IMO.
 
I'm sorry I thought the OP asked about UV sterilizers. I'll respect your opinion about the MH shortening the cycle since I've never cycled a tank without lights .

Edit:
ichthyoid;626594 wrote: I was referring to wavelength's from lighting, not a UV filter. The light from a Metal Halide for example, can inhibit or destroy nitrifying bacteria as well, per the references.

As to rate of colonization, I have used bacteria cultures and cycled in ~5 days using ammonia at ~4ppm, as well as the long (4-6 week) method with fish. Both work, I just prefer using the bacteria. Both are preferable to do without light of any kind, IMO.

Yes I've seen short cycles that were very successful. The addition of fish after the either method of cycle is where I see many mistakes made, too many fish too quick.The bacteria does not have time to colonize with such a drastic increase in the bioload then the ammonia levels get too high.
 
Thanks guys. I really appreciate the in-depth information. I've been using Stability for a week now (the time frame on the bottle). I haven't turned on the uv yet, so I guess I'll just see how well the Stability has worked & then start running it. The Stability bottle says you can start adding fish & other creatures immediately after starting using it, as long as you finish the dosages. I don't trust that though, so I'm trying to be as patient as possible.

Thanks again,
Brad
 
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