Biological filter question

[mobot]

I'm running a 30g refugium on my 90g tank. After the initial filter pad water drains through a chamber with bio balls and I was thinking of adding some Fluvial Biomax. I'm wondering if that chamber needs to be dark though. I run an LED grow light 24 hours a day in the planted section. Is the LED going to slow/stop bacterial growth in the first chamber? If so, any suggestions on how to shade it?

[pcsb23]

No you don't need to shade it. I'd have the lights off in the refugium during the main tanks photo period.

[mobot]

No you don't need to shade it. I'd have the lights off in the refugium during the main tanks photo period.

Really? Everything I've read has said stick with a 24 hour photo period. What's the benefit to opposite photo periods?

[pcsb23]

I guess it depends on what you have in the refugium, if it is normal plants (even fast growing stems etc) then they need a downtime too. If it is an algal scrubber type affair then yep needs 24/7 light, but that isn't really a refugium. Just my opinion (though the plants do benefit from a dark period). Also if you are running co2 then you will achieve better stability with opposite photoperiods. But if it isn't broken, don't fix it :)

[mobot]

Right on. Makes sense. Will probably also cut down on green algae. Thanks. I've got some bamboo and Wisteria in there now. Any suggestions on something better? Water is at 84 degrees.

[tbmeck]

A 24 hour photo period is not needed as it could result in algae issues. Plants produce Co2 at night, which is why some people choose to run their freshwater refugium opposite their planted tanks. While their planted tanks rest, the refugium plants will produce oxygen, and consume the Co2 being produced by the plants in the tank, and vice versa. If you run them both at the same time the increased Co2 levels at night could cause your Ph to drop too much if your water is not buffered. Large Ph swings can be stressful on fish. Personally I run my freshwater refug at the same time my tank lights are on. I do not carry enough plant bio-load to cause much of a Ph swing if any, plus I maintain my Kh at 5-6 which is more than enough to prevent a large ph swing.

[LEXUSGS350]

https://www.youtube.com/watch?v=yEzLaRljYtc
https://www.youtube.com/watch?v=O6UbWS3hfe4

[mobot]

It seems like, especially since I'm running CO2 during the day only, I might be better served by running my refugium light on the same photoperiod as my tank. That way all plants are making O2 at the same time. While the CO2 is off at night the plants will maintain the PH. Make sense?

[pcsb23]

It seems like, especially since I'm running CO2 during the day only, I might be better served by running my refugium light on the same photoperiod as my tank. That way all plants are making O2 at the same time. While the CO2 is off at night the plants will maintain the PH. Make sense?Why this concern over pH? Neither the fish nor the plants will give a flying fig about what the pH is doing.

[Tres]

Reefers tend to run their fuges on a reverse light cycle to their tank, in order to stabilize pH. If adding Co2 then it likely makes sense not to however, or run in 24/7 still as at least some Co2 will be produced by the tank itself at night, though I'm not sure your plants will be able to utilize light 24/7.

[Loosir]

Why this concern over pH? Neither the fish nor the plants will give a flying fig about what the pH is doing.

I'm also thinking of adding stem plants to my sump and leaving the display tank without plants. Are you saying this is safe? No issues with ph? I've been trying to read a lot and I keep seeing posts about not having plants with young discus. Is this a non issue if they are only in the sump and not the display? Thanks

[pcsb23]

I'm also thinking of adding stem plants to my sump and leaving the display tank without plants. Are you saying this is safe? No issues with ph? I've been trying to read a lot and I keep seeing posts about not having plants with young discus. Is this a non issue if they are only in the sump and not the display? ThanksThe fish only care about having clean, warm water and good food. Provide those in abundance and they will be fine. The plants need the same, except their food is carbon, nitrogen, potassium and phosphor (NPK, yet everyone forgets to mention carbon, which is the most important!). Provide what each need and they will prosper, don't provide for one and it is likely that both could suffer.

[Loosir]

Thanks