Tank struggles

[Motoman89]

Hey guys, I am looking for some advice on my tank issues. My plants don't seem to be growing very well but the algae is doing just fine. Here are some details.

Started tank up about a month ago, doing regular water changes of about 40% every week or two. All my water tests seem to be good. Currently only have 10 fish (5 guppies, 1 cory and 4 shrimp (algae eating type). Lighting is with 2x50W RC41, 4000 lumen bulbs over a 30 gal high tank. 12 hour lighting cycle from 7am until 7pm. Substrate is pool sand with flourish tabs under the sand but have not added any since start up. I was dosing with Big Al's all purpose plant food but since the algae got out of hand a few weeks ago I stopped that and haven't added anything.

So as the pics show my plants aren't growing at all. First pic is when we first added the fish and plants after the tank ran for two weeks. I am wanting a low tech tank as I don't really want to get into CO2 again. My java moss hasn't even started to attache my wood or coconut shell after 4 weeks and it should have in my mind. Any thoughts and guidance would be great.

Thanks.

[hoseki]

What do you mean by all my water test seems to be good? What have you tested and how many test have you done? What test kit are you using? Best to post up your test result.

[lucius]

I know you mentioned that you don't want to get into CO2 again but it wasn't clear if it's liquid or pressurized CO2.  You can try dosing Flourish Excel CO2 if you don't want to go the hardware route.

[wolfiewill]

We need more details. There is not enough info to go on. What testing seems good? And, what kind of lights do you have? Perhaps a picture of the light with the power off? And I you have a 30 tall, how far above the tank are the lights?

Both the ferts you are using are micro fertilizers and provide no nitrate or phosphate for plant growth. And without carbon in some form, you'll have a tough time. I'd suggest more algae grazers but algae is not the source of the problem, it's a symptom.

[Christianloug]

I find there are mixed feelings about pool sand, but in my personal opinion I don't recommend it for plants. Also would recommend having a shorter light cycle so the algae doesn't grow as much, I personally have 9 hours on and 15 hours off. As others have said, other than that i think more detail is needed

[Plants245]

A 12 hour lighting regime seems long (I use to do it and had algae problems) ... I reduced down to 7 hours and have had much better growth (at least from a low tech perspective) -- it sucked to come to terms with reducing lighting, but limited algae is better, in my opinion.

What are your parameters: Nitrate, Phosphate, pH, KH, GH?

A limited quantity of any nutrient, will allow algae to utilize the excess of the missing nutrient - we will never reach the perfect "balance" to nutrients, because it varies by day as plant density changes, but we can try to limit it.

I would definitely scrape off the algae during each weekly WC.

Cheers