diatoms

[Johanna]

Anyone here know how to best combat diatoms? I've always had some in the main tank, but it's become a problem lately and I want to get rid of it. I don't think it's the sand or stones leaching silicates because the problem has recently gotten much worse. I'm wondering if there's some issue with the tank or water that's causing it? Could it be that feeding more beef heart causes it? I haven't tested phosphates or silicates and will if I can't find any obvious reason... but first I'd like to see if I can alter some conditions like feeding or lighting to reduce the diatoms. Plecos keep the swords and crypts and flat surfaces mostly clean but stem plants and thin leaves are looking quite awful already 2-3 days after water changes and wiping everything as clean as possible. There is very little if any other types of algae, so the problem is just with the diatoms.

[brewmaster15]

If you increased your feedings and didnt increase your water changes that could possibly explain the change to the diatom population. Generally when a tank suddenly has a problem after being stable its always a good idea to consider everything that has changed.

[Johanna]

Not sure if I have increased the amount of food per se, but I ran out of the seafood mix and it's no longer available at my lfs, and the new discus don't eat mysis or artemia so now the majority of their diet consists of beef heart. I'm still feeding 2-3 times a day but it could be the bioload has still increased.

[bluelagoon]

Beef heart is high in phosphates there for more WC's are required.

[Johanna]

Beef heart is high in phosphates there for more WC's are required.

Thanks, that's something I suspected it might be and started changing every 2 days, to see if it makes a difference. But I don't think I can keep that up permanently so I'm going to look for some filter media that could remove phosphates if that seems to be the cause.

[jwcarlson]

I can't imagine feeding beefheart and not changing water daily. It's SO messy even if they're eating "all" of it. I'm not even sure how people manage feeding it with canisters or other filtration that aren't readily able to be cleaned. I was just running sponge filters when I was feeding it and those things got dirty pretty quickly.

[Johanna]

I can't imagine feeding beefheart and not changing water daily. It's SO messy even if they're eating "all" of it. I'm not even sure how people manage feeding it with canisters or other filtration that aren't readily able to be cleaned. I was just running sponge filters when I was feeding it and those things got dirty pretty quickly.

Beef heart looks less messy than the seafood mix I had but idk, it probably still produces more waste. I hand feed the beef heart in chunks while still partially frozen, and the fish nibble on it as it thaws. Small pieces escape but usually the smaller discus or dwarf cichlids catch them before they hit the bottom. And I have very greedy and fat omnivore plecos. In the small tanks I unplug the filters for feeding... in the big tank I just feed away from the intakes and it doesn't seem to be a problem with frozen foods or granules, flakes on the other hand break into small bits that tend to get sucked in before all of it is eaten.

[bluelagoon]

Sometimes low light will cause diatoms instead of the more advanced green algae. Plus if using BH regular once a day or every other day 50% or more WC's are best. But there are other foods high in proteins like Al's black worms or even freeze dried bloodworms, if black worms are not available. It's not uncommon to have to wipe the glass down weekly for diatoms, algae and biofilm. Surely, you can afford something better than beefheard if you wanna avoid lots of WC's.

[Johanna]

I ordered Seachem Purigen and phosphate/silicate remover to see if it helps. More wc's have helped a little maybe.

I have thought about the lights. There is plenty of light ( 2 x Aquael Leddy Slim Marine 36 W / 10 000k) but is it the 'wrong' kind? When I bought these, the seller assured me the cold white would be ok for a freshwater planted tank despite being designed for a marine tank (I don't particularly like the yellow shade of so-called daylights and the purple of 'plant' lights). I have since added two plant spectrum spotlights on the ceiling above to help grow the pothos and also provide more suitable lighting for the aquatic plants but I don't know if it's still enough/the right combination. I'm not an expert in lights so if anyone can offer an opinion, it'd be appreciated!

[DiscusTankmates?]

Sounds like your tap water may be high in silicates and feeding more has made it worse.

[Johanna]

Ok, this problem seems to have mostly disappeared for now. More water changes.... but then again, I was gone for 4 days and there was a 5 day gap between wc's and there was no increase in diatoms when I came back. Wonder if the phosphate remover already did it, or something in the tap water changed? Or, perhaps the natural light cycle changed as the day is rapidly getting shorter - maybe there's less sunlight directly hitting the tank. Anyway, I'm just glad my plants are mostly green again.