I am switching my filter media from a carbon base to a bio base media. I found some bio-media by Rena called bio-chem stars, and ceramic cylinders. Just wondering what anyones thought's where on those two types of biomedia for a canister filter. Also my lighting in my 40 gallon planted. I have been running my 2 T8 ZooMeds Plantgrowth 17 watts from 7 A.M. - 7 P.M. The 2 T5 HO's are Hagen Life-Glo 6700K's and those i've been running from 11 A.M. - 5 P.M. I have four current white LEDs running in the P.M. for moonlighting effect. Do the lighting parameters sound alright for a low - moderate light planted tank?

on the T8 ZooMeds Plantgrowth 17 watts, you are fine...on the T5 Hagen Life-Glo 6700K, may be a bit much. 6700°K high-noon full spectrum bulbs provide intense illumination, emits a natural white light that penetrates deep into aquariums. The deep aspect of this bulb is really only for a tall tank, say over 24 inches deep. The problem is, it can and probably will produce algae as time goes by.

T8 ZooMeds should only run about 8-10 hours; the T5 Hagen should run about 4 hours if that (unless others have better information than what I am telling you, I wouldn't run these at all)

as for the moonlighting effect, no problem with this lighting

bio-chem stars and ceramic cylinders are fine, it will provide plenty area for good bacteria to accumulate in the thousands all over the bio media. Trick is, anytime you rinse out the canister, never rinse any of the bio-media.

so outside of the T5 Hagen lighting, it all looks good.

First of all, there are a few basic reasons to have high output (HO) lighting: depth of the tank, plant species you plan on keeping, and growth rate desired.

A 13 watt 20 inch T-2 Bulb (6400 K) produces 950 lumens which is 73 lumens per watt in a very small space with low wasted green/yellow light energy that is often found in other power compact lights. These are very useful for small to medium planted aquariums. The newest generation T2 Lights require less watts to provide the same useful light energy (in particular required by plants & coral) than all other lights except for LED. The T2 will even exceed a comparable T5 light by about 20%.

If you could provide the names of all your plants I can help you much better. Once this is understood, you'll know exactly if you need a high output bulb (s) or just a plain one or one without high output.

High output is usually for tanks with a huge array of plants and that are at least 24 inches deep. T2 will suffice for the tank you have. Plus in case in the future if you decide to go to a bigger tank, a T2 can actually be extended via an attachment.

Hope this info helps. Let me know. By the way, you can keep your T5, just don't be surprised if you get a lot of algae in the future (good thing about T5 is it keeps the water from getting too hot, this is a plus side if the tank has too much lighting).

Let me know how this goes, always look forward to see progress made