Clarification of light colours and best combinations, please

[cool_breeze]

Hey folks. My first post on this forum.

I've had an aquarium for about a year. It is my first one, and consists of a pretty basic setup:
A 50L freshwater tank, with gravel substrate, bogwood for structure, and an airstone with mini pump.
Illumination is provided by a T5 24W light consisting of three 8W tubes; x2 white, x1 blue, which is mounted roughly 100mm above the water surface.
Water temperature is around 21 C daytime, bit less at night as the heater is on a timer.
I have several easy-care green plants in the tank (Anubias - attached to a piece of bogwood, Myriophyllum, Vallisneria, and a couple of moss balls). I was feeding with a liquid additive to the water; 8 drops every week. Now I'm using another liquid additive - Tetra's PlantaMin - and dosing the water every month at the recommended rate. I was advised this was adequate feeding for these plants.
I have x3 Cherry barb, x3 White cloud mountain minnow, and a few shrimp in there.
I'm doing a water change every 2 - 3 weeks. I also lightly vacuum the gravel.

The plants all started off strongly, but now all are faltering in varying degrees. The Vallisneria's established leaves are pale. It is sending up new shoots, but they don't develop beyond 30mm in length. After trebling in size the Myriophyllum is now gradually turning yellow. The Anubias' established leaves are lush and green (though brown at the edges), but new leaves start off almost white before recovering their colour later on. It is slow growing generally. The moss balls look healthy but don't seem to grow at all.

I think light spectrum could be the issue. White tubes are what I have been using up to now, for no other reason than they were what was supplied with the light unit I have. Recently, one of the white T5 tubes has blown. I am looking to replace it, but have since been advised that Red is the best colour of light to stimulate plant growth.
Should I have x1 white and x1 red, x2 red, or stick with x2 white.. and I don't even know what the blue light is for (I never use it. I thought perhaps it was to provide night-time illumination)..?

Any advice gratefully received.

Thanks. Phil

 

[Sacha]

*popcorn*

 

[candymancan]

Blue is Actinic 460nm.. dark purple is Actinic 420nm.. Mostly used for salt water corals they makes the colors POP.. Some people including me like using the blue Actinics for fresh water because they also make colors pop out.. White bulbs depending on what they are could be 10k lights which are more blueish white, or 6700k lights which are more yellowish white.. And Pink/red bulbs are for plants specificly.

Moss balls in my opinion never grow I don't like those things.. As for the white leaves on your plants you are either low on iron or something else.. You should be dosing ferts if your plants do that. What kind of "white" bulb do you have and what are the red/pink ones.. A name would help a lot

 

[pepedopolous]

Rightyho, welcome!

You need to dose some ferts that contain NPK (nitrates, phosphates and potassium). For a beginner Tropica Specialised is good http://tropica.com/en/plant-care/liquid-fertilisers/specialised-fertiliser/ Follow the manufacturers instructions but divide the weekly dose into daily amounts, basically 1-2 ml per 50 litres per day. You can do no harm by adding even more than that.

Secondly, you could dose liquid carbon (Seachem Flourish Excel or Easylife Easycarbo), again something like 1ml per 50 litres per day. This stuff is harmful if you overdose it or get it on your hands, wallpaper etc. It kills some plants such as Elodea and Vallisineria. Replace them with something else.

Thirdly, for plant growth you need not worry about the colour of the light. Neutral white (often labelled as 6500k) makes most plants and fish look nice under it. I don't have much experience with T5s but I think it would help you a lot to reduce the light to a maximum of 2 bulbs for 7-8 hours a day.

Lastly, you don't mention a filter. You need water movement in the range of 10x the volume of the aquarium per hour. If you have low light and easy plants this is less important but it can't be ignored. An air stone isn't enough! External filters are best but an internal or hang-on filter will do especially for smaller tanks.

Also you must change the water more often, as much as 50% weekly is common. As you aren't adding extreme ferts or pressurised CO2 gas maybe every 2 weeks is OK.

Do all of these things and the plants should respond well. If you are serious about this hobby, you need to do some research such as reading the articles on this forum.

Cheers,

P

 

[Edvet]

Maybe have a read of our "Tutorial section", lot's to learn, more than can be covered in one post........