[catchthecarp]

I'm hoping someone here can point me in the right direction to get my nitrates out of the red zone and eliminate my diatom issue. I started this tank in Dec 2014 and nitrates have always registered high using the API test kit, from 50-80 (red). A 50% water change will lower them to orange but after a few days they are back to red. I have lots of plants and live stock is within guidelines. I use root tabs (Osmocote+) and PPS from GLA daily. Here are my tank specs and water parameters.

100 GL
Lighting - BLM 6500K Photo period is timed (8 hrs)
Filtration - Fluval 306 and 406
CO2 - Yes - Drop checker is lime green

Water parameters:
PH- 6.6
KG- 5.0
GH- 12.0
Nitrite- 0
Nitrate- 60
Ammonia- 0

I've ordered Seachen Denitrate to see if that will help. I've also orderd an API Phosphate test. I do not know what the silicate content of my water is, are the test kits sold commercially reliable?

Below are some pics of my Anubias plants, they grow new leaves but are always coated in brown diatoms. If you look at the pics below there also a white substance on some of the leaves, I have no idea what this is or the cause.

I have not idea what the white coating is on my anubias leaves.

 

[dukydaf]

That does not look like diatoms to me. Does it rub off easily ? If not it is a form of red algae. The white stuff can be from biodecalcification, getting CO2 from carbonates... Anubias can do this.

What plants are present in your aquarium ? Can we have a full tank pic ?

The osmocote could be leaching the N or perhaps overfeeding ? lack of plant growth ? Anyway I would advise against using a denitrate product. A healthy growing plant mass is the best way to keep algae away.

 

[catchthecarp]

I can rub it off but not easily, I've used a scrub pad made for acrylic and gently scrubbed them. It always grow back in a few weeks. It looks red but it's more a rust brown color. I have mostly beginner plants, anubias, swords, java fern, vals, crypts, and some stem plants(no idea what they are). I haven't used a lot of root tabs, 8 in total. The nitrate levels have always been high, they haven't budged and have not changed since adding the root tabs and starting the PPS dosing. I feed the fish once a day. My fish are all healthy and I haven't lost any in a long time. I have 4 large Siamese algae eaters and 1 brushy nose pleco but they don't make a dent in it. My light is on a dimmer so I'm going to start by reducing the light intensity a bit. Below is a pic of the entire tank and a shot of the right side.

[/url]

 

[Maryland Guppy]

The nitrate levels have always been high, they haven't budged and have not changed since adding the root tabs and starting the PPS dosing.

Are you you using the nitrate free recipe that Edward recently listing on the PPS Pro site.
If not I would recommend it. Seems you have enough of a bio-load from fish.

Do you monitor PO4 in your tank?
Having noticed myself that if I keep PO4 levels @ 1ppm more NO3 is absorbed by plants.

Just some of my observations, I use a modified PPS-Pro recipe with extra PO4.

 

[catchthecarp]

No, I have not heard of the nitrate free recipe, I will definitely look that up, thanks for the tip. I have not tested or monitored for PO4, I ordered an API phosphate test kit over the weekend, should be here soon.